Which of the following shows that polynomials are closed under subtraction when polynomial 3x2 + 4 is subtracted from x2+ 2x + 5? −2x2 + 2x + 1 may or may not be a polynomial 2x2 − 2x − 1 will be a polynomial −2x2 + 2x + 1 will be a polynomial 2x2 − 2x − 1 may or may not be a polynomial