Answer: (x + 2).
Explanation:
To determine whether an expression is a factor of a polynomial, we can use synthetic division. Here's the synthetic division for this problem with (x + 2) as the divisor:
-2 | 1 2 -9 -18
|-2 0 18
|__________
1 0 -9 0
Since the remainder is 0, we know that (x + 2) is a factor of the polynomial. Therefore, the answer is (D) (x + 2).