Answer:
D
Explanation:
The opposite of a negative is a positive.
The opposite of a positive is a negative.
The opposite of -9xy2 is 9xy2, and only C and D have 9xy2.
The opposite of 6x2y is -6x2y, and only A, B, and D have -6x2y.
The opposite of -5x3 is 5x3 and only A, C, and D have 5x3.
Which one reoccurs? D.
Hence D is the answer.