What is $\int_0^1 \frac{\tan ^{-1} x}{1+x^2} d x$ equal to?

• A

  $\frac{\pi^2}{8}$
• Correct answer
  B

  $\frac{\pi^2}{32}$
• C

  $\frac{\pi}{4}$
• D

  $\frac{\pi}{8}$

Hence, the correct answer is option: 'B'.