$\int_0^\pi x \sin ^7 x \cos ^6 x d x=$

• A

  $\frac{8 \pi}{1002}$
• B

  $\frac{18 \pi}{1003}$
• Correct answer
  C

  $\frac{16 \pi}{3003}$
• D

  $\frac{6 \pi}{3003}$

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