i vote for B, but have no very clear objections against other choices
may be because of ||-ism
they sometimes lose money ....and they are unable to raise

in A when there is a rise... is not bad but to me inferior, to the short-term rates rise-in B

Dnt u feel "they" in B is ambiguous?????

for sure i feel that they is not perfect here,
but honestly i saw many times that Gmat very often violates pronoun issues.
and never does so on ||-ism,

Since savings banks have to use short-term deposits to finance long-term fixed-rate mortgage loans, they sometimes lose money when there is a rise in short-term rates and, on the other hand, they are unable to raise the rates on their mortgages.

(A) when there is a rise in short-term rates and, on the other hand, they are unable to raise
(B) when short-term rates rise and they are unable to raise
(C) when a rise in short-term rates occurs and, correspondingly, there is no rise possible in
(D) with a rise in short-term rates, and they are unable to raise
(E) with short-term rates on the rise and no rise possible in

First thing that comes in mind is parellism after seeing this question
to use and to raise

This eliminates except B and D......a rise in short term rates and short term rates....

B is better to use ...SO OA is B

if the option D is rewritten as

when short term rates rise, and they are unable to raise.... would that be correct????

Acc. to my understanding it would be correct as the part they are unable to raise the rates on their mortgages is an IC. Is my reasoning correct??

Please correct me if wrong....

Thanks
Gautam