$f\left(x\right)=x^3-3x+5$ then $f\left(\sin \frac{{\displaystyle 3\pi }}{{\displaystyle 2}}\right)+f\left(\cos \frac{{\displaystyle 3\pi }}{{\displaystyle 2}}\right)=$

• A

  12

• B

  0

• C

  1

• D

  2