You can take x = a, 2y = b and then can apply the binomial theorem.
The expansion of given expression is given by: 
Option D:  is
 is 
<h3>What is binomial theorem?</h3>
It provides algebraic expansion of exponentiated(integer) binomial.
According to binomial theorem,

<h3>How to use binomial theorem for given expression?</h3>
Taking a = x, and b =2y, we have n = 7, thus:

Thus, Option D:  is correct.
 is correct.
Learn more about binomial theorem here:
brainly.com/question/86555