If $\int _ { 0 } ^ { 1 } f ( x ) d x = \pi,$

Multiple Choice

If $\int _ { 0 } ^ { 1 } f ( x ) d x = \pi,$ then $\frac { \pi ^ { 2 } } { \int _ { 1 } ^ { 0 } f ( x ) d x }$ is

A) $- \pi ^ { 2 }$
B) $- \pi$
C) $\pi$
D) $\pi ^ { 2 }$
E) Impossible to determine