Unlike the brain of a chickadee

Question

Unlike the brain of a chickadee that lives in the wild, where it avoids predators and
forage for its food, a caged chickadee does not appear to produce nearly as many
new neurons in the hippocampus.

(A) wild, where it must avoid predators and forage for its food, a caged chickadee
does not appear to produce nearly as many new neurons in the hippocampus

(B) wild, avoids predators, and forages for its food, that of a caged chickadee does
not appear to produce nearly as many new neurons in the hippocampus

(C) wild, avoiding predators and foraging for its food, far fewer neurons are produced
in the hippocampus of that of a caged chickadee

(D) wild, and avoids predators foraging for its food, the production of new neurons
is far less in the hippocampus of a caged chickadee

(E) wild, avoiding predators and foraging for its food, the production of new neurons
will be far less in the hippocampus of that of a caged chickadee

What is wrong in the sentence? How is the Best Option became the correct answer?

OA B

ErikaPrepScholar · Answer

Whenever we see a comparison work like "unlike", we should start looking for issues of parallelism — comparisons must always compare two parallel things. (An example: "The eyes of sharks are better than fish," does not work because it compares "eyes" to "fish". We need "The eyes of sharks are better than the eyes of fish" or "The eyes of sharks are better than those of fish".)

Here, we have "Unlike the brain of a chickadee that lives in the wild". So we need to be comparing this to another brain — we can predict that we want to compare to "the brain of a caged chickadee". While we don't get those exact words, B does give us:

"Unlike the brain of a chickadee that lives in the wild ..., that of a caged chickadee ..."

Here, "that" is a pronoun that stands in for the subject of the sentence, "brain", just like "those" stood in for "eyes" in our example above. So we are comparing a brain to another brain here. All of the other answer choices do not have parallel comparisons.

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BTGmoderatorDC · Answer

ErikaPrepScholar wrote:Whenever we see a comparison work like "unlike", we should start looking for issues of parallelism — comparisons must always compare two parallel things. (An example: "The eyes of sharks are better than fish," does not work because it compares "eyes" to "fish". We need "The eyes of sharks are better than the eyes of fish" or "The eyes of sharks are better than those of fish".)

Here, we have "Unlike the brain of a chickadee that lives in the wild". So we need to be comparing this to another brain — we can predict that we want to compare to "the brain of a caged chickadee". While we don't get those exact words, B does give us:

"Unlike the brain of a chickadee that lives in the wild ..., that of a caged chickadee ..."

Here, "that" is a pronoun that stands in for the subject of the sentence, "brain", just like "those" stood in for "eyes" in our example above. So we are comparing a brain to another brain here. All of the other answer choices do not have parallel comparisons.

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