Đạo hàm của hàm số: y = sin2x.cos^4 x - cot(1/x^2) - sin2x.sin^4 x

A. $\cos 2x.4{\cos }^{2}x+\frac{1}{{\sin }^2{\displaystyle \frac{1}{x^2}}}-\cos 2x4{\sin }^{3}x$

B. $2\cos 4x+\frac{2}{x^3{\sin }^2{\displaystyle \frac{1}{x^2}}}$

C. $2\cos 4x+\frac{2}{x{\sin }^2{\displaystyle \frac{1}{x^2}}}$

D. $2\cos 4x-\frac{2}{x^3{\sin }^2{\displaystyle \frac{1}{x^2}}}$