Thunderclouds form when warm, moist air rises into cooler air above

Thunderclouds form when warm, moist air rises into cooler air above, because either the ground is warmer than usually or because the interaction of two air masses, one warm and one cold, forces warm air to rise.

(A) because either the ground is warmer than usually or because
(B) because either the ground is warmer than usual or because of
(C) because of either the ground being warmer than usual or because
(D) either because of the ground's being warmer than usually or because of
(E) either because the ground is warmer than usual or because

Why is D wrong ? IMO because of followed by a verb is wrong, as in option D contains verb "being". Please let me know if my reasoning is correct

Hello.

D is wrong because:

1. "ground's being warmer" = ground is being warmer. Why we use present continuous? Present simple is correct.

2. Because of + noun/noun phrase. But the "second" because of + clause (because of the interaction of two air masses, one warm and one cold, forces warm air to rise.). That's wrong.

Hope it helps.

So does that mean because of +"clause" is permissible in GMAT ? I am under the impression that because of+"Noun or Noun Phrase" is the only permissible structure

gmat will not force us to realize that "than usual " is correct and that "than usually" is incorrect.

This question is based on Parallelism.

The correlative conjunctions ‘either-or’ is used in the sentence. The appropriate pair is used in every option. However, the other rule of parallelism of correlative conjunctions is that each of the pair of conjunctions must be followed by the same part of speech.

In Option A, ‘either’ is followed by the noun (the ground) and ‘or’ is followed by the conjunction (because). Since parallelism is not maintained, Option A can be eliminated.

The same error is repeated in Option B, so, this option can be eliminated.

Option C has the same lack of parallelism; this option is also worded in a very clumsy manner. So, Option C can be eliminated.

In Option D, the parallelism is maintained as both conjunctions of the pair are followed by the conjunction ‘because’. However, the construction of this option is incorrect as the last part of the sentence is a clause – “the interaction of two air masses” is the subject and “forces” is the verb – and the phrase “because of” can only begin a phrase and not a clause. So, Option D can be eliminated.

Option E maintains parallelism and is concise. Therefore, E is the most appropriate option.

Jayanthi Kumar

"being" isn't the actual problem in (D), I guess!
It's the possessive `ground's` that is the potential issue.
The ground's what?
Ground's grass, dirt, soil?

Posted from my mobile device

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.