A polynomial is given below. 3 x 6 + 2 x 4 − x 3 + 7 Which statement must be true about this polynomial? A. It has exactly 3 roots (including any repeated roots) that may be real or complex numbers. B. It has exactly 3 roots (including any repeated roots) that must be real numbers. C. It has exactly 6 roots (including any repeated roots) that must be real numbers. D. It has exactly 6 roots (including any repeated roots) that may be real or complex numbers.