The Colorado trading community paid a huge premium when it chose

34. The Colorado trading community paid a huge premium when it chose to invest the entire pension corpus into technology stocks on July 15th 2001 of firms who were known to make large number of stock buybacks and ESOP purchases.
A. of firms who were known to make
B. when it is known that firms made
C. at which firms are known to have made
D. that firms are known to be making
E. at which it is known that firms had made

Can someone please explain what is the error with option A?

Couldn't understand the question at all! Please help in comprehending the same

between B and C , I think C is right.

OA (option C) conveys the following meaning:

Firms are known to have made large number of buybacks and purchases at technology stocks ("at which"). The Colorado trading community invested into these technology stocks and while doing so paid a huge premium.

Somebody please explain the options

This is more on the meaning side, So i made an investment of my pension fund on those stocks which will give me the maximum return, but my stocks didn't perform well so i had to pay a price for it.

With that in mind, lets look at the options
A. of firms who were known to make
Who is only used to present people -> eliminate

B. when it is known that firms made
When is incorrectly used here -> Out

C. at which firms are known to have made
Since i will make a profit at some stocks, this relates with what i had stated.

D. that firms are known to be making
They are still not making any profit -> Out

E. at which it is known that firms had made
Why are we using past perfect tense here ?? -> Out

sayantanc2k
is the use of "at which" correct here?

Please explain when can we use this term correctly

It has to be that the use of “who” in answer choice A is wrong.

Aside from the fact that there’s an “a” missing between the answer choice and the remaining sentence, and that “investing at companies” sounds strange, C seems somewhat reasonable...

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Can you please explain in detail and with other examples the meaning for the "at which" used in this case, please??

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