After all the research that has been conducted in the last 30 years, it is readily apparent that there are, without question, a wealth of good reasons to do aerobic exercise regularly
A. there are, without question, a wealth of good reasons to do aerobic exercise regularly
Singular verb "IS" should be used for singular noun "Wealth". Hence Incorrect.

B. there are, without question, a wealth of good reasons to exercise aerobically regularly
Singular verb "IS" should be used for singular noun "Wealth". Use of adverb "Aerobically" changes the original intent. Original intent was "aerobic exercise regularly". How one can exercise AEROBICALLY???? What kind of method is it?? Hence Incorrect.

C. there are, without question, a wealth of good reasons to engage regularly in aerobic exercise
Singular verb "IS" should be used for singular noun "Wealth". Hence Incorrect.

D. there is, without question, a wealth of good reasons to engage regularly in aerobic exercise
Correct

E. there is, without question, a wealth of good reasons to do regular aerobic exercises
Use of adjective "Regular" changes the original intent. Original intent was "aerobic exercise regularly". What kind of exercises would be categorized REGULAR??? Hence Incorrect.

Seems 'a wealth of good reasons' similar to 'a lot of good reasons'.

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Hello Everyone,
I have recently started preparing for GMAT and SC is my weakest point. Can anyone suggest/share some tips to prepare for SC.

Thanks,
Vandana

A wealth of good reasons is singular.

Only D and E have SV agreement between. All the others use ‘are’ to refer to ‘wealth’. E changes the meaning by shifting ‘regular’ to describe ‘aerobic exercises’ rather than the act of doing them. Hence, D is the right answer

I think start with a solid Verbal course that sets your fundamentals right. Gradually work your way up to higher levels. How are you with Quant ?

KAPLAN OFFICIAL EXPLANATION

Step 1: Read the Original Sentence Carefully, Looking for Errors
Sometimes the subject of a clause will appear after the verb, as is the case in this sentence. In
the underlined subordinate clause, the subject is “a wealth” and the verb is “are”—and both are
underlined, so we must check for agreement. (The noun “reasons” cannot be the subject because
it is part of the prepositional phrase “of good reasons,” which modifies the subject.) “Wealth” is a
singular noun, so we need a singular verb; “are” is plural, so we have a subject-verb agreement error.

Step 2: Scan and Group the Answer Choices
(A), (B), and (C) retain the verb “are.” (D) and (E) both change the verb to “is.”

Step 3: Eliminate Choices Until Only One Remains
We know that “are” is incorrect, so we can eliminate (A), (B), and (C). Choice (E) changes “do aerobic
exercise regularly” to “do regular aerobic exercises,” which alters the meaning of the sentence in
an illogical way. Here we want the adverb “regularly,” which modifies how often a person should
engage in exercise, not the adjective “regular,” which modifies the noun “exercises,” indicating
that the exercises themselves should be “regular” or “normal.” Because the correct answer must
fix any existing errors without changing the meaning of the original sentence, (E) is incorrect, and
(D) is the correct answer.

After all the research that has been conducted in the last 30 years, it is readily apparent that there are, without question, a wealth of good reasons to do aerobic exercise regularly

A. there are, without question, a wealth of good reasons to do aerobic exercise regularly

-- SV agreement error

B. there are, without question, a wealth of good reasons to exercise aerobically regularly

-- SV agreement error

C. there are, without question, a wealth of good reasons to engage regularly in aerobic exercise

-- SV agreement error

D. there is, without question, a wealth of good reasons to engage regularly in aerobic exercise

-- Correct

E. there is, without question, a wealth of good reasons to do regular aerobic exercises

-- Adjective changes the meaning; we need the adverb 'regularly'
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A. there are, without question, a wealth of good reasons to do aerobic exercise regularly
is should be the right verb usage since it's pointing towards wealth therefore out

B. there are, without question, a wealth of good reasons to exercise aerobically regularly
aerobically doesn't make any sense therefore out

C. there are, without question, a wealth of good reasons to engage regularly in aerobic exercise
Similar reasoning as A

D. there is, without question, a wealth of good reasons to engage regularly in aerobic exercise
The meaning and the verb usage is perfect therefore our answer

E. there is, without question, a wealth of good reasons to do regular aerobic exercises
regular it's distorting the meaning therefore out

Therefore IMO D