Express the Given Quantity in Terms of Sin X or Cos

Multiple Choice

Express the given quantity in terms of sin x or cos x.
- $\cos \left( \frac { 3 \pi } { 2 } - x \right)$

A) $- \sin x$
B) $\sin ( - x )$
C) $\sin x$
D) $\cos x + \sin x$