Which of the following shows that polynomials are closed under subtraction when two polynomials, (4x2 − 8x − 7) − (3x2 − 5x + 16), are subtracted?
A)x2 − 3x − 23; will be a polynomial
B)x2 − 3x − 23; may or may not be a polynomial
C) x2 − 13x + 9; will be a polynomial
D) x2 − 13x + 9; may or may not be a polynomial