题目下列说法正确的是（ ）A.多项式2x3−4x−12x^{3}-4x-12x3−4x−1的常数项是111B.−3πx2y35-\frac{3πx^2y^3}{5}−53πx2y3的次数是666C.−2x2y3-\frac{2x^2y}{3}−32x2y的系数是−2-2−2D.多项式x2+2x+1x^{2}+2x+1x2+2x+1是二次三项式知识点：多项式;整式加减运算法则章节：未标注
