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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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The sentence tells us two things about Quartzite.
1. It is considered one of the most pristine Paleozoic mineral deposits.
2. It is believed to be metamorphosed since the deposition of the Triassic era.

The sentence connects two independent sentences by just using a comma. The correct way to connect to independent sentences is by using comma and FANBOYS or by using a semicolon. On the basis of this we can eliminate options A, D ,and E.

Now we are left with options B and C. Option B is correct because the sentence uses "since" which in this sentence is used to indicate time. Whenever since is used as an indicator of time. It talks about an action that started in the past and is continuing in the present.
For ex. I have lived in London since 2005.
And option B correctly shows an action that started in the past and is continuing in the present and also connects two independent clauses correctly. "and it is believed to have been metamorphosed since the deposition of the Triassic era."

Therefore option B is the correct answer.
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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 - comma dividing IC is wrong
(B) and it is believed to have been - wrong tense and "it" is quartzite? as we talking about depositS
(C) and that is believed to be - long and awkward
(D) which was, it is believed, - which was and it is? wrong
(E) which are believed to be - which clearly talking about depositS and "are" is correct verb
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Right answer. (B) and it is believed to have been
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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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Here we are talking about the metamorphosis of Paleozoic mineral deposits and not just quartzite, hence the only option which fits is (E) which are believed to be
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Q is considered (Present Tense)
A) past tense used with since
B) it refers to Quartzite (ok) , with since Present perfect is ok
C) Same as A
D) Past tense referring to something which is still believed
E) which refers to Plural deposits (SV issue)
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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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A past participial phrase can be used to non restrictively modify a noun. The phrase is used directly before or directly after the noun. The phrase is separated from the noun and other sentence elements using commas.
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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 - be metamorphosed is incorrect - continous verb required
(B) and it is believed to have been - metamorphosed is a continuous process so have been is a benefit for this option
(C) and that is believed to be - `that` is incorrect
(D) which was, it is believed, - was metamorphosed since - incorrect - continous verb required
(E) which are believed to be - now the second part of the setance refers to all the mineral deposits and not only the quartzite

option D correct
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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.


Here the intended meaning of the sentence is that the Paleozoic mineral deposits are believed to be metamorphosed since the deposition of the Triassic era. Also the quartzite found in the Santa Ana Mountains is considered one of the most pristine Paleozoic mineral deposits.

Now let's look at the options:

(A) believed to be
Here the phrase 'believed to be' is used after a comma and normally it should point to the nearest noun i.e. 'the mineral deposits'. That is the intended meaning of the sentence. However, it could also point to 'quartzite'. The meaning then becomes vague.
But let's keep this for now.

(B) and it is believed to have been
Here 'and' is used to connect two independent clauses which is okay, but use of the passive form of the verb i.e. 'it is believed to have been metamorphosed since the deposition of the Triassic era' is vague. What is believed to have been metamorphosed? Is it quartzite? or is it the mineral deposits The meaning is unclear here. INCORRECT

(C) and that is believed to be
Here comma + 'and' is used to connect an independent clause with a dependent clause. The dependent clause 'that is believed to be metamorphosed since the deposition of the Triassic era' conveys a vague meaning when used stand alone and we don't know what is 'that' referring to here. INCORRECT

(D) which was, it is believed,
Here comma + which modifier is used that by rule should point to the nearest noun. Here that noun is 'mineral deposits'. Note how the verb 'was' is used with the plural noun. That violates the SV agreement rule. Also in the latter clause 'which was, it is believed, metamorphosed since the deposition of the Triassic era', simple past is used with 'since'. This should have been in the progressive tense form and not simple past. INCORRECT

(E) which are believed to be
Here like in option D comma + which modifier is used that by rule should point to the nearest noun. Here that noun is 'mineral deposits'. Note how the verb 'are' is used with the plural noun. That meets the SV agreement rule. This choice makes more sense than option A as the intended meaning is matching here. We can now cross out option A. CORRECT
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(B) , which is modifier error so we can eliminate C/D
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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
whether mineral deposits or the quatzite (as the antecedent for 'believed to be')-- is unclear

(B) and it is believed to have been
correct pronoun usage..it correctly refers to only singular precedent ie, the quartzite found in the Santa Ana Mountains...use of have been justifies the usage of 'since' in the non-underlined portion

(C) and that is believed to be
wrong idiomatic usage considering the usage of 'since' in the non-underlined portion

(D) which was, it is believed,
wrong S-V agreement for the 'mineral deposits'

(E) which are believed to be
wrong idiomatic usage considering the usage of 'since' in the non-underlined portion

(B) is the CORRECT answer
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The phrase "metamorphosed since the deposition of the Triassic era", provides a time frame for metamorphose of the quartzite. "Since" implies that something started in the past and is still continuing into the present day. For this one requires the present perfect tense. The only answer choice which is in the present perfect is B, identifiable by the use of "have been".

Answer B
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A)This option sounds correct, but it is not clear what believed is modifying and does not provide a clear connection between the quartzite and the belief. It is unclear what is being believed in this context.

(B) This option is grammatically correct, but it adds unnecessary repetition with "it is believed" after the conjunction "and." The sentence becomes wordy and less concise.

(C) This option is also grammatically correct, but it introduces the pronoun "that" without a clear antecedent. It is not clear what "that" is referring to in the sentence, leading to ambiguity.

(D) Correct Choice. The phrase "which was" introduces a relative clause that provides additional information about the quartzite found in the Santa Ana Mountains. The phrase "it is believed" correctly indicates the belief or understanding about the metamorphosis of the mineral deposit. 'It' is just a place holder pronoun. There is no ambiguity hence, best option amomg the given

(E) which are believed to be
This option uses "which are believed to be" to modify "the quartzite found in the Santa Ana Mountains." However, the sentence refers to the quartzite as a singular mineral deposit, so the plural form "which are believed to be" is incorrect.
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This question tests us on pronoun and verb tense
A. Unclear. What is believed? Also, verb is in wrong tense|
B. Correct. Fanboy "and" connects 2 clauses, pronoun "it" clearly connect to the antecedent "The quartzite". "to have been" correctly points to the event happened in the past
C. "that" is unclear
D and E incorrecly use "which" after comma to modify "Paleozoic mineral deposits"
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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
We can't use "to be" here, it must be "to have been".

(B) and it is believed to have been
Correct, although I am not happy with "and", but this is the best answer among the answer choices.

(C) and that is believed to be
The use of "to be" is faulty, we shouldn't use "to be" here.

(D) which was, it is believed,
Although the grammar here is correct, the problem here is in the meaning of the sentence; it is first saying something as a fact with "was" and then saying it's not actually a fact but is just a belief. So, the meaning is faulty.

(E) which are believed to be
the use of both "are" and "to be" is faulty. We can't use either here.

Answer is B.
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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
Sounds like the mineral deposits are metamorphosed rather than the quartzite. Eliminate option.

(B) and it is believed to have been
Correct option.

(C) and that is believed to be
Same as option A. Also i think has/have would be a better option because the sentence uses since. Eliminate option.

(D) which was, it is believed,
Same as option A. Eliminate option.

(E) which are believed to be
Are is wrong. We require is. Eliminate option.

Option B.
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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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(A) believed to be - Incorrect it seems to be modifying mineral deposits. Correct target here should be the quartzite found in Santa Ana mountains.
(B) and it is believed to have been - Incorrect S-V agreement error
(C) and that is believed to be - Correct
(D) which was, it is believed, - Incorrect usage of which seems to be modifying mineral deposits
(E) which are believed to be - Incorrect same error as D
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Option: B

D, E modify the wrong noun owing to which touch rule. A is a comma splice. B and C remain. C isn't logical; no referent for "that"
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