What is the coefficient of [tex]x^{7}[/tex] in the product of the two polynomials below?
([tex]x^{4}[/tex] - [tex]3x^{3}[/tex] + [tex]6x^{2}[/tex] - 2x =1) ([tex]4x^{3} -5x^{2} +2x)[/tex]

A. 0
B. 2
C.4
D. 7