设 $f\left(x\right)=\{\begin{array}{c}1,x>0\\ 0,x=0\\ -1,x<0\end{array},g(x)=\{\begin{array}{c}1,x\mathrm{为有理数}\\ 0,x\mathrm{为无理数}\end{array},$则 $f\left(g\right(\pi \left)\right)$的值为

A．

1

B．

0

C．

-1

D．

$\pi$