Answer:
X^2-49 is the correct option
Explanation:
(x+7)(x-7)
x*x-7x+7x-7*7
x^2-49
The product of both gives x^2 − 49
which implies that option last option is wrong x^2+49 since the sign in between is negative sign
The option x^2 + 14x + 49 is also wrong because the -7x+7x gives zero not 14
The first option is also wrong because -7x+7x gives zero not -14
All in all, the correct option is x^2+49, the second option