Answer:
option (B) is correct.
Mystery term has to be

Explanation:
Given :
is the GCF of the polynomial

We have to find the mystery term '?'
GCF stands for greatest common factor. GCF is the highest common factor that can divide all the given terms.
Here,
is the GCF of the polynomial

For unknown term , we have two conditions,
1) it has to be multiple of 4
2) it must have
as a factor.
So out of given options only
is a term which is both multiple of 4 and has
as a factor.
Thus, Mystery term has to be

Thus, option (B) is correct.