the sum of -15x^2 -5x + 11 and another polynomial expression is -9x^2 + 3x -10. What is the other polynomial expression?

A. 24x^2 + 8x - 8

B. 6x^2 + 8x - 21

C. -24x^2 + 8x + 8

D. -24x^2 + 8x - 8​