The answer is C.
(4x^4-14x^3) * (6x^2-21x) simplifies to 24x^6-168x^5+294x^4.
A.) It simplifies to 12x^4-42x^3, not the same as our answer so, A is not right.
B.) 12x^5-42x^4, also not right.
C.) 24x^6-168x^5+294x^4 , which is the same as the simplified version of (4x^4-14x^3) * (6x^2-21x).
D.) Is not the least common multiple because it is the same equation.
Hope this helps!
