Evaluate the Improper Integral or State That It Is Divergent $$\int _ { 0 } ^ { \infty } \frac { 36 \left( 1 + \tan ^ { - 1 } x \right) } { 1 + x ^ { 2 } } d x$$

Multiple Choice

Evaluate the improper integral or state that it is divergent.
- $$\int _ { 0 } ^ { \infty } \frac { 36 \left( 1 + \tan ^ { - 1 } x \right) } { 1 + x ^ { 2 } } d x$$

A) $18 \pi$
B) $18 \left( 1 + \frac { \pi } { 2 } \right) ^ { 2 }$
C) $36 \ln \left( 1 + \frac { \pi } { 2 } \right)$
D) $18 \pi \left( 1 + \frac { \pi } { 4 } \right)$