7t^4x7t^4

a. 49t^8**
b. 14t^4
c. 49t^16
d. 14t^8

it isnt correct

To simplify the given expression, you can multiply the coefficients (numbers) and add the exponents of the variables.

In this case,

7t^4 * 7t^4 = (7 * 7) * (t^4 * t^4) = 49 * t^(4 + 4) = 49t^8.

Therefore, the correct answer is option a. 49t^8.

Correct.