Simplify: (−7a−4b7)(3a2b−4) (1 point) Responses −21a8b28 the fraction with numerator negative 21 and denominator A to the 8th power b to the 28th power −21a6b3 the fraction with numerator negative 21 and denominator A to the 6th power b cubed −21a2b3 the fraction with numerator negative 21 A squared and denominator b cubed −21b3a2 the fraction with numerator negative 21 b cubed and denominator A squared

The correct answer is −21a2b3, which represents the fraction with numerator -21 and denominator A squared times b cubed.