Answer:
(2n + 7) (2n +7)
Step-by-step explanation:
To solve this problem we need to factorize 4n^2 + 28n +49 as shown below
thus, after factorization we see that first option is correct one
(2n + 7) (2n +7)
we can validate this by expanding it
2n (2n +7) + 7 (2n+7)\
=> 4n^2 + 14n + 14n + 49 = 4n^2 + 28n +49 (which is equal to the problem stated expression)