Some bird species at first begin migrating from east to west because

OFFICIAL EXPLANATION



THE PROMPT




THE OPTIONS

• the sentence is grammatical

• it also contains glaring redundancy
→ the phrase at first begin is redundant. We do not need at first. Concision really is a thing.

• the style of the sentence is not polished
→ the phrasing rambles (is wordy)
→ the diction (word choice / arrangement) is clumsy and awkward
→ the phrasing does not make a lot of sense on first read. (I understood what was happening after I read option B.)

• strange meaning
→ daylight hours decrease along a similar westward pattern
Something can't really decrease "along" a pattern.
Something can decrease IN a pattern.
The trajectory from east to west is not really a pattern.
The birds initially fly in a westward direction, not "along a westward pattern."

I really do not like this sentence.
That said, I never eliminate an option on the first pass on the basis of redundancy or style or both.

We will keep A but look for a better option.


• the sentence is better than option A, though not entirely pristine
→ no redundancy issues

→ "that is the direction" refers to west.
West is indeed a direction to which the word that refers.
See Oxford Dictionary online, here.

→ standalone pronoun that?

When that is used as a pronoun, it:
1) is a relative pronoun that introduces a relative clause (the house that Jack built)
2) is a "copy maker" pronoun (Pollution in cities is worse than that in rural areas), or
3) is a demonstrative adjective that "points" to a noun, this way: That path leads to a river; the other one leads to a meadow.

Now, will GMAC allow a different instance of that, one in which the word that is a standalone pronoun?*
Answer: at some time soon, probably—but never very often.

I do not recall having seen an official question in which that was a standalone pronoun.
On the other hand, especially in the last few OGs, I do not remember a question in which this issue was tested.

Moreover, in formal English and occasionally on the GMAT, another demonstrative adjective, those, can stand alone and refers to a select group of people.

Furthermore, in OG 2020, for the first time of which I am aware, GMAC allowed a standalone this to refer to the entire previous clause.
SPOILER ALERT: That official question is here.

Finally, the usage of that is efficient and clear, contributing to the rhetorical force of option B.

Option B avoids redundancy, strange phrasing, and wordiness.
Option B also communicates with a precision that option A lacks.
The redundancy in option A is glaring.

Make the call. Option B is better than Option A.
ELIMINATE A
KEEP B


• construction error: do not use and to join a dependent and an independent clause
→ The word while introduces a dependent clause.
→ The dependent clause cannot stand on its own and does not have the weight of an independent clause.
→ Do not use AND.
The word and joins items of equal grammatical weight, such as two independent clauses.
The word AND should not be used to join a dependent and independent clause.
ELIMINATE C


• Meaning error created by the conjunction because
→ the conjunction Because suggests that the migration of the birds from east to west causes them to turn south.
Wrong. They turn south to find warm weather.

• because and since should not be paired in the same clause.
They mean the same thing. The sentence should not contain two instances of words that mean "because" in the same clause.
ELIMINATE D


• A verb is missing
→ the subject species is not connected to a working verb in the first clause
→ beginning is not a working verb
ELIMINATE E

The best answer is B.


COMMENTS

I am awarding kudos to all who posted because this question is a lot harder than it seems at first glance.

The reasoning in these posts is good and often creative.
What I see is that people are indeed reading.
People who read high end English consistently should be put off by option A and pulled towards B.

If you did not choose option B, do not worry.
Learning does not happen without mistakes.
This SC is an exercise in subtlety.

And this thread?
Nice work.



**If you like technical terms: can that be a demonstrative pronoun?
Demonstrative pronouns are related to demonstrative adjectives in that they both refer to objects that are identifiably near or far away. A demonstrative adjective must be followed by a noun. A demonstrative pronoun is not followed by a noun.

Ideal Split: Tough call between A and B

A: Correct – even though it is wordy

B: This choice is a contender because direct verb form MIGRATE is used but I am not sure about the antecedent of pronoun THAT

C: Fragment – No working verb for subject “the direction”

D:
1) Illogical meaning of phrase: it is the direction that daylight hours decrease
2) FROM is also missing just before EAST

E: Fragment – No working verb FOR subject “Some bird species”

My answer is (B). It took me 01:50.

(A) It is rather hard to fully comprehend what this sentence means by "because daylight hours decrease along a similar westward pattern".
"at first" and "begin" are redundant.

(B) The sentence is concise and clear.
What is the antecedent for "that" in "that is the direction"? Probably "west".

(C) "and" should be deleted, for two reasons.
(1) "and" should be appropriately used to construct an coordination sentence: IC1 + Comma + FANBOYS + IC2. (IC stands for Independent Clause). Here, a subordination sentence is needed.
(2) How about deleting the first word "While"? The sentence structure would be correct (as a coordination sentence), but the transition from IC1 to IC2 calls for "but“ rather than "and".

(D) In this subordination sentence, the use of "because" fails to capture the relationship between subordinated clause and main clause.

(E) "they" should be deleted as the sentence already has its subject "Some bird species".

(B) is correct IMO


Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but they then turn south to head towards warmer weather.


A) Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but

Eliminate A for following reasons
The sentence intends to present some fact about some bird species, so it is best to use present tense especially when we have present tense in non underlined portion.
At first and begin makes the sentence look redundant and superfluous

B)At first, some bird species migrate from east to west because that is the direction in which daylight hours decrease, but
Correct

C) While some bird species migrate east to west at first, the direction that daylight hours decrease, and
No main clause
Sentence is awkward and ungrammatical

D) Because some bird species migrate east to west since it is the direction that daylight hours decrease,

use of Because and since together is wrong - Eliminate

E) Some bird species, beginning by migrating from east to west because this is the direction that daylight hours decrease,
Present participle should modify the preceding clause, but the sentence is structured in such a way that there is no preceding clause.
Eliminate

Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but they then turn south to head towards warmer weather.


A) Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but - Use of begin is wrong. Should be began

B) At first, some bird species migrate from east to west because that is the direction in which daylight hours decrease, but - Correct

C) While some bird species migrate east to west at first, the direction that daylight hours decrease, and - Incorrect contrast

D) Because some bird species migrate east to west since it is the direction that daylight hours decrease, - use of that is incorrect.

E) Some bird species, beginning by migrating from east to west because this is the direction that daylight hours decrease, - No verb for some bird species.

Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but they then turn south to head towards warmer weather.


A) Some bird species at first begin migrating from east to west because daylight hours decrease along a similar westward pattern, but Incorrect

misplaced at first, a similar westward pattern compare what? this choice wordy

B) At first, some bird species migrate from east to west because that is the direction in which daylight hours decrease, but Correct

that indicate east to west

C) While some bird species migrate east to west at first, the direction that daylight hours decrease, and Incorrect

while can be use as conjunction, no need additional 'and'

D) Because some bird species migrate east to west since it is the direction that daylight hours decrease, Incorrect

it refers to what
there is no cause and effect relationship in sentence

E) Some bird species, beginning by migrating from east to west because this is the direction that daylight hours decrease, Incorrect

Some bird species is a fragment
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The official explanation is here.
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