Hello everyone,

The other day, I came across a choice question as follows:

The heavy rainfall has caused vegetable prices to rise daily (     ) the
last two months.
a. by     b. for     c. since     d. during

At first, I thought that "for" should be the only right answer,
but on second thoughts,I am beginning to suspect that "during" may also
be correct.
Am I wrong?

Thanks in advance.

SIRAISI Tomio