ANSWER
The correct answer is D.
EXPLANATION
If we express the monomial,

as product of primes, we obtain:

If we express the monomial

as product of primes we obtain:

The least common multiple of these two binomials is the product of the highest powers of the common factors.
The LCM is


Therefore the correct answer is D.
Answer:
a exponent 2-b exponent 2
ab