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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:33
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A, C, D and E are all satisfying choices and we keep them,
but B just sounds better and therefore it's our answer
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:35
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(A) believed to be
This is ambiguous

(B) and it is believed to have been
This sounds more likely to be the correct option
It correctly uses the right pronoun 'it'
It talks in the past perfect tense .. something that happened in the past. The sentence has one past tense before it

(C) and that is believed to be
Use of that is ambiguous

(D) which was, it is believed,
The comma placement is wrong
Use of which was is unclear
The framing makes the sentence awkward and confusing

(E) which are believed to be
Subject is singular - so it cant be which are
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:39
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be - deposits are believed
(B) and it is believed to have been - plural when 'quarzite is collective - singular'
(C) and that is believed to be - correct
(D) which was, it is believed, - refers to deposits
(E) which are believed to be - refers to deposits

as since is used - have been
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:41
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It should be past -ed have been since - present perfect construction
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:45
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"metamorphosed" is supposed to modify 'The quartzite." Only Option B correctly represents this modification. So, Option B is the answer.

Options A, C and E modify "pristine Paleozoic mineral deposits," and there is a SV error in Option C. Option D is awkward and illogical.
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 09:58
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
(B) and it is believed to have been
(C) and that is believed to be
(D) which was, it is believed,
(E) which are believed to be


 


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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be- Part participle not required. Eliminate A.
(B) and it is believed to have been- "It" is incorrectly modifying quartzite.
(C) and that is believed to be - "and that" doesn't have any parallel structure in the sentence. Eliminate C
(D) which was, it is believed, - The first half of the sentence is present tense. We need the same tense in the second half unless and until there is a logical transition. Eliminate D.
(E) which are believed to be - "which" is correctly modifying to "deposits". Correct Answer.
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 10:13
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

its clear that quartzite is believed to be metamorphosed since the deposition of the Triassic era. Thus, placing a "which" right after the comma will mess up the meaning as the "which" will then refer to Paleozoic mineral deposits. Therefore, eliminate D and E

option A - Portion after the comma is a dependent clause. Therefore, the comma present is not a comma splice and the sentence as a whole sounds fine though its not flawless. so we hold on to A

Options B and C use conjunction AND after a comma. This is necessary only if the clauses being joined are independent clauses. The portion before the comma is an independent clause. Now, lets look at portion after ",and"
option B - it is believed to have been metamorphosed since the deposition of the Triassic era - independent clause. "it", a singular pronoun, refers to quartzite. "have been" is present perfect tense. While it is fine to say it was believed since past and continues to be believed so in present, "have" is used for plural cases. Here, quartzite is singular. so, eliminate B
option C - that is believed to be metamorphosed since the deposition of the Triassic era - independent clause. "that", a singular pronoun, refers to quartzite. "to be" is simple present tense. all sounds good. It eliminates whatever discomfort we sense in A. therefore the answer is C, the better option.
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
Incorrect. The modifier - believed to be metamorphosed since the deposition of the Triassic era - incorrectly modifies the noun present before the comma, i.e. Paleozoic mineral deposits. However, it needs to modify quartzite .

(B) and it is believed to have been
Correct. The use of "since" in the non underlined part of sentence suggests that the action of believing extends from certain past time until the present. And so the use of present perfect tense is correct , not simple present tense.

(C) and that is believed to be
Incorrect. The use of "since" in the non underlines part of sentence suggests that that the action of believing extends from certain past time until the present. And so the use of present perfect tense (have been) is correct , not simple present tense (is).

(D) which was, it is believed,
Incorrect. The use of "which" incorrectly modifies the noun present before the comma, i.e. Paleozoic mineral deposits. However, it needs to modify quartzite .

(E) which are believed to be
Incorrect. The use of "which" incorrectly modifies the noun present before the comma, i.e. Paleozoic mineral deposits. However, it needs to modify quartzite .
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 10:22
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be - incorrect tense
(B) and it is believed to have been - CORRECT
(C) and that is believed to be - incorrect tense
(D) which was, it is believed, - incorrect tense
(E) which are believed to be - incorrect tense
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

We have to correct the underline part to correctly reflect the tense as well as to make the flow of the sentence clearer. The metamorphosis started in the past, i.e, since the Triassic era, and the quartzite is still undergoing this process.

(A) believed to be: doesn't reflect that the action started in the past and is still ongoing.
(B) and it is believed to have been: correct, since it uses "have been" to reflect the sequence of actions.
(C) and that is believed to be: that adds a reference error and complicates the sentence.
(D) which was, it is believed,: unnecessarily wordy and doesn't correctly show the current scenario
(E) which are believed to be: usage of "are" is incorrect
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Bunuel
The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
(B) and it is believed to have been
(C) and that is believed to be
(D) which was, it is believed,
(E) which are believed to be


 


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We have since in the non underlined portion hence the tense should be present continuous.

(A) believed to be

The sentence uses present tense instead of present continuous.

(B) and it is believed to have been

Correct

(C) and that is believed to be

no referent for that

(D) which was, it is believed,

incorrect use of tense 'was'

(E) which are believed to be

The sentence uses present tense instead of present continuous.

IMO B
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 10:46
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be Incorrect Two independent clauses should be separated by coordinating conjunction and a comma
(B) and it is believed to have beenCorrect "and" coordinating conjunction and the use of past participle is preferred with the use of "since".
(C) and that is believed to beIncorrect comma is missing
(D) which was, it is believed,Incorrect Use of relative pronoun is incorrect
(E) which are believed to beIncorrect use of the relative pronoun is correct and it should be rather separated by comma
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
- No conjunction between two independent clauses. Incorrect!
(B) and it is believed to have been
-Correct!
(C) and that is believed to be
- "That" refers to what? Incorrect!
(D) which was, it is believed,
- "which" incorrectly refers to the deposits
(E) which are believed to be
- same as D
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 11:02
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Bunuel
The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
(B) and it is believed to have been
(C) and that is believed to be
(D) which was, it is believed,
(E) which are believed to be


 


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believed to be incorrectly refers to paleozoic mineral deposits which is incorrect. A is out.

it correctly refers to quartzite, which is correct. Also have been is correctly used here since here is a time marker (since the deposition of the triassic era). Hence Keep B.

that correctly refers to quartzite, which is correct. But use of present perfect tense is preferable instead of simple present tense. Hence Keep C is out.

In ans choices D&E usage of which is incorrect since which refers to paleozoic mineral deposits.

Hence B is correct ans.
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Meaning: This kind of quartzite is considered X and is believed to be Y.
-The thing that "was metamorphosed" is quartzite, not the deposits (because quartize must be metamorphosed before becoming the most pristine Paleozoic mineral deposits)=> We can eliminate E)
-D) we have the relative pronoun "which" substitute for its preceding noun-"deposits". But "was" is wrong since you need a plural verb for a plural noun=>S-V agreement error=> Eliminate D
-B), C) we have parallelism error. Which eventually leaves us to A
-A) is correct since we can use past participle after a comma to modify for the preceding clause. It explains why quartize is considered "the most pristine".
=>A
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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
ed modifier modifies nearest modifier - Paleozoic mineral deposits while it should have referred Quartzite
(B) and it is believed to have been
It here just refers to singular noun quartzite and have been notifies that metamorphosis has been continuing from the past. Since is a clue for usage of have been and hence is the answer
(C) and that is believed to be
that requires the copy and the refers to singular noun quartzite, however to be does not make sense as since is a clue for usage of have been
(D) which was, it is believed,
Which here refer to nearest noun mineral deposits and does not seem appropriate as meaning requires quartzite to have undergone metamorphosis. Also usage of is look incorrect as it requires plural verb with Paleozoic mineral deposits
(E) which are believed to be
Which here refer to nearest noun mineral deposits and does not seem appropriate as meaning requires quartzite to have undergone metamorphosis
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Correct answer: (A) believed to be.

This is a participle that correctly refers to the singular noun, "quartzite." All other options used either the wrong tense or too many unnecessary modifiers.
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Answer is B

The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
believed modifies deposits, but it should modify quartzite. Incorrect.
(B) and it is believed to have been
it refers to quartzite, Thus, correct.
(C) and that is believed to be
that is wrong, for no parallelism is found.
(D) which was, it is believed,
was is the wrong verb tense.
(E) which are believed to be
Again, same mistake as A.
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Around the World in 80 Questions (Day 1): The quartzite found in the 17 Jul 2023, 11:29
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subject is The quartzite singular we need singular verb
eliminate B, E
option D uses past perfect which was ; incorrect
between option A & C

option C is correct because of usage of subordinator conjunction and
and that is believed to be


option C is correct

Bunuel
The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.

(A) believed to be
(B) and it is believed to have been
(C) and that is believed to be
(D) which was, it is believed,
(E) which are believed to be


 


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The quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits, believed to be metamorphosed since the deposition of the Triassic era.
Since, the quartzite is considered ...... and is believed to be..... even today - use of simple present tense makes more sense.
(A) believed to be
Incorrect - because the phrase "believed to be" fails to specify the time frame or present state of quartzite
(B) and it is believed to have been
usage of present perfect tense is incorrect - "have been" can't be used for describing the present state of quartzite.
(C) and that is believed to be
is believed is past tense - incorrect due to reasons given above
(D) which was, it is believed, - incorrect - it changes the meaning - which was suggests the quartzite doesn't exist now
(E) which are believed to be
correct - usage of present tense conveys the meaning correctly and effectively. It connects the quartzite with the belief about its metamorphosis since the deposition of the Triassic era.
Answer E
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