The herring gull population in the North America is now thirty times larger than in the beginning of the century.

(A) than in
(B) than they were at
(C) than it was at
(D) compared to that of
(E) compared to what they were at

Choice C!

Let's simplify this question:

[x] population is now 30 times larger than the [x] population in the beginning of the century.

So how can we express this properly.

Choice A -- Is incorrect because we are just saying that the population is greater than "in the beginning of the century" -- its an incorrect comparison. It's missing the pronoun reference. Population must be compared to population.

Choice B -- they were -- population is singular

Choice C -- correct "it" refers to the population

Choice D -- "Larger compared to" -- awkward...Larger than is better

Choice E -- uses plural -- wrong

C is the correct choice.
First examining the choices, we can eliminate D and E as we need a "than to follow larger" here.

Secondly, we are referring to a specific time instant in history : the beginningof the century. So we need an "at" . (if the construction was without "the" : beginning of century, "in" would have been more appropriate). So we can eliminate A.

Lastly we need a singluar verb with population. Hence can eliminate B.


Left with C .


Crick

Main Issues:

1) Parallelism: X & Y should be parallel.
2) Idiom: Correct idiom is "larger than". Incorrect: "larger compared to".
3) Comparison: Population is being compared for 2 different times.

A. than in - Wrong: Proposition "at" should be used instead of "in".
B. than they were at - Wrong: Plural "they" can't be used to refer to singular "Population".
C. than it was at - Correct
D. compared to that of - Wrong: 1) Idiom 2) Don't need another copy "that". 3) Distorted Meaning: "population of the beginning..."
E. compared to what they were at - Wrong: Idiom 2) Plural "they" can't be used to refer to singular "Population".
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the only error in choice A is "in". we have to use "at the beginning". this is purely idiomatic.

if we change "in" into "at", choice a is more consice than choice c.