Let a Denote the Area Enclosed by the Equation $y = \sin x$

Let A denote the area enclosed by the equation $y = \sin x$ and the x-axis with $x \in [ 0 , \pi ]$ Then A is

A) $\frac { 1 } { 2 }$
B) 1
C) $\frac { 3 } { 2 }$
D) 2
E) $\frac { 5 } { 2 }$