Answer:
Option C
Explanation:
$f(x)=\begin{cases}x^{2}+3x-7, & x > 0\\h(x) ,& x < 0\end{cases}$
f(x) is odd function, then h(x)=?
forr odd function
$h(-x)= -h(x) \Rightarrow h(-x)= (-x)^{2}-3x-7$
$\Rightarrow$ $ h(-x)=x^{2}-3x-7$
$\Rightarrow$ $-h(x)=-[x^{2}-3x-7] \Rightarrow $ $-x^{2}+3x+7$