Sentence Correction

The speculative fever of the Roaring Twenties infected rich and poor alike; vast quantities of people were dangerously overextended, credit was absurdly easy to obtain, and most brokerage houses required only ten percent cash for stocks bought on "margin."
(A) rich and poor alike; vast quantities of people were dangerously overextended
(B) both rich and poor alike; large amounts of people dangerously overextended themselves
(C) rich and poor alike; great numbers of people were dangerously overextended
(D) both rich and poor alike; vast amounts of people dangerously overextended themselves
(E) both rich and poor; great quantities of people were dangerously overextended

The answer is C but is great numbers of people correct?
experts kindly clear my doubt

Well, it depends on the context. The usage great numbers of people is correct when you are referring to multiple sets of numbers. But in this question, none of the remaining answer choices seem to fit. People though collective can be counted. We say many people, not much people. So that rules out all the remaining answers - amount and quantity don't fit in this context. What say?

Advice:
Please try not to give the OA or atleast use spoiler to hide the OA when posting questions. Will help others solve the question the right way before answering. Also, a good practice to quote your source for the question (was religiously followed some time ago on the forum).

The best option would obviously be large number/numbers of people, but since thats not given I would pick C because all others are surely incorrect usage for quantity.

nidhis.1408 wrote:
The answer is C but is great numbers of people correct?
experts kindly clear my doubt

Always remember we are looking for the best option, not the perfect one!

POE to reach C!