Find the derivative of arcos 4x with respect to x.

• A. -4 / [1 – (4x)^2]^2
• B. -4 / [1 – (4x)]^0.5
• C. 4 / [1 – (4x)^2]^0.5
• D. -4 / [(4x)^2 – 1]^0.5