Sentence Correction

It is well known in the supermarket industry that how items are placed on shelves and the frequency of
inventory turnovers can be crucial to profits.
(A) the frequency of inventory turnovers can be
(B) the frequency of inventory turnovers is often
(C) the frequency with which the inventory turns over is often
(D) how frequently is the inventory turned over are often
(E) how frequently the inventory turns over can be

I know the ans and rationale behind the ans of this Q. I used the same logic as mentioned in : https://www.manhattangmat.com/forums/og- ... -t897.html

I am trying to find as many errors as I can to get more conceptual clarity in SC:

What i want to discuss/ know is "can be" vs "often", when comparing D and E? Original sentence uses "can be". Thus, using "often" (means mostly) will change the tone. right?

I chose B.

Can you share the OA when possible.

OA is E