VaCeFe
Bunuel
Bunuel
The ways children adapt to new situations tell psychologists more about how they absorb information than the children’s I.Q.s.
(A) how they absorb information than
(B) how one absorbs information than
(C) how children absorb information than do
(D) absorbing information than
(E) their information absorption than do
MANHATTAN REVIEW OFFICIAL EXPLANATION:
Choices A and E are ambiguous. It is not clear to whom the ‘their’ and ‘they’ are referring. Choice D is equally ambiguous because you do not know who or what is absorbing information. Choice B is missing the necessary auxiliary verb ‘do’. Choice C is the correct answer.
Can you please explain the difference between the usage of "than do"and "than"? I got confused with that.
Thanks!!

VaCeFe , the phrase "than do" is an inverted verb-subject structure that the GMAT occasionally uses.
In English, we often use the word do (does, does so, etc.) to avoid having to repeat a verb or verb phrase.
1) Progressives
approve of government spending to help the needy more than conservatives
approve of government spending to help the needy."2) Progressives
approve of government spending to help the needy more than conservatives
do.
• in this case, "do" stands in for "approve of government spending to help the needy."
• We use "do" the second time to avoid repeating the whole verb phrase.
The GMAT often reverses the structure of the SECOND verb.
3) Progressives
approve of government spending to help the needy more than
do conservatives.
If we do not add the second verb, if we leave off "do" in this instance, we get a rather funny (and ungrammatical) result.
4)
INCORRECT: Progressives approve of government spending to help the needy more than conservatives.
• meaning #1: Progressives approve of government spending to help the needy more than progressives approve of conservatives.
• meaning #2: Progressives approve of government spending to help the needy more than conservatives approve of government spending to help the needy.
In any event, the ambiguity is unacceptable.
We must include "do."
This question is similar.
Correct #1: The ways children adapt to new situations
tell psychologists more
about how children absorb information than the children's I.Q.s
tell the psychologists about how children absorb information.
Correct #2: The ways children adapt to new situations
tell psychologists more
about how children absorb information than the children's I.Q.s
do. [tell psychologists . . . .]
Correct #3: The ways children adapt to new situations
tell psychologists more
about how children absorb information than
do the children’s I.Q.s.
INCORRECT #4: The ways children adapt to new situations tell psychologists more about how children absorb information than the children’s I.Q.s.
MEANING:
Ways in which children adapt tell psychologists more about how children absorb information than
those adaptive ways tell psychologists about children's I.Q.s
The other four options have errors that do not require us to decide between
do and
than do.
If we have to decide, however, we add or omit the "do" and check to see which sentence creates clearer meaning.
In this instance, sentence #3 is far more clear than sentence #4.
In addition, without the verb "do," the sentence is ambiguous and unacceptable on the GMAT.
If you can't decide and both options are grammatically correct otherwise, pick the option that includes "do."
HERE is an excellent topic thread on GMAT Club about comparisons, inverted structure in comparisons,, ellipsis (omitting long verb phrases), and substitution (with words such as "do").
On that page is a lot of information about when we may use "do," when we should use "do," when we cannot use "do," and much more.
Hope that helps.