Find the Rate of Change of the Function $f ( x ) = - x + \sin x$

Multiple Choice

Find the rate of change of the function $f ( x ) = - x + \sin x$

A) $\tan x \sec x - x$
B) $\cos x + 1$
C) $\cos x - 1$
D) $- \cos x - 1$
E) $- \cos x + 1$