Answer:
D: a² + ab + b²
Explanation:
The general formula used for factoring a difference in cubes is;
a³ - b³ = (a - b)(a² + ab + b²)
Thus, the factors are either;
(a - b) or (a² + ab + b²)
Looking at the given options, the only one that is a factor is (a² + ab + b²) which is option D.