Choose the correct simplification and demonstration of the closure property given: (3x3 + 2x2 − 5x) − (8x3 − 2x2). 5x3 + 2x2 + 5x; is a polynomial 5x3 + 2x2 + 5x; may or may not be a polynomial −5x3 + 4x2 − 5x; is a polynomial −5x3 + 4x2 − 5x; may or may not be a polynomial