Which statement justifies that 3x2 − 2x − 4 multiplied by 2x2 + x − 3 obeys the closure property of multiplication? The result 6
x4 − 2x2 + 12 has a degree of 4. The result 6x4 − 2x2 + 12 is a trinomial. The result 6x4 − x3 − 19x2 + 2x + 12 is a polynomial. The result 6x4 − x3 − 19x2 + 2x + 12 has a degree of 4.