Verified Answer :

TSO

\(3x^2(2x+3)(x-7)\\\\3x^2(2x^2 +3x-14x-21)\\\\3x^2(2x^2-11x-21)\\\\6x^4-33x^3-63x^2\)

The answer is A.

\(5(2x+3)^2\\\\5(4x^2+12x+9)\\\\20x^2+60x+45\)

The answer is C.