Which of the following is $d y / d x$ if $y=\cos ^{2}\left(x^{3}+x^{2}\right) ?$
(A) $-2\left(3 x^{2}+2 x\right)$
(B) $-\left(3 x^{2}+2 x\right) \cos \left(x^{3}+x^{2}\right) \sin \left(x^{3}+x^{2}\right)$
(C) $-2\left(3 x^{2}+2 x\right) \cos \left(x^{3}+x^{2}\right) \sin \left(x^{3}+x^{2}\right)$
(D) $2\left(3 x^{2}+2 x\right) \cos \left(x^{3}+x^{2}\right) \sin \left(x^{3}+x^{2}\right)$
(E) $2\left(3 x^{2}+2 x\right)$