Answer: The correct option is
(B) the product of x and a factor not depending on x.
Step-by-step explanation: We are given to select the correct verbal description of the following expression:

We can see that
the above expression 'E' contains the product of x and (2y + 7z)².
The expression (2y + 7z)² does not contain x, so it is independent of x.
Therefore, the expression 'E' contains the product of x and a factor not depending on x.
Thus, (B) is the correct option.