Choose the most appropriate words to fill in the blanks of the given sentence.
They said they were not going to ______ any gifts for their ceremony ______ for donations to charities.

Option B: Correct.

Here there are exactly two words used to fill in the blanks to form a meaningful sentence. 

We have to first, know the precise meaning of the two words.

Then, understand what the sentence is trying to convey.

And, then place the words.

accept means to take something willingly

except means to exclude something

The sentence is trying to convey that people in question will not be taking any gifts but they will be taking donations.

So accept and except will be used. Hence, option B is correct.