Let a Denote the Area Enclosed by the Graph $f ( x ) = \cos x,$

Multiple Choice

Let A denote the area enclosed by the graph $f ( x ) = \cos x,$ the x-axis, and the lines $x = 0$ and $x = \frac { \pi } { 2 }$ . By part 2 of the Fundamental Theorem of Calculus, A is

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