The correct option is option (c) $p=\pm 4$
The given points are $A(4, p)$ and $B(1,0)$ and $A B=5$.
=> $\left(x_{1}=4, y_{1}=p\right)$ and $\left(x_{2}=1, y_{2}=0\right)$
$\mathrm{AB}=5$
$\Rightarrow \sqrt{\left(x_{2}-x_{1}\right)^{2}+\left(y_{2}-y_{1}\right)^{2}}=5$
$\Rightarrow \sqrt{(1-4)^{2}+(0-p)^{2}}=5$
$\Rightarrow(-3)^{2}+(-p)^{2}=25$
$\Rightarrow 9+\mathrm{p}^{2}=25$
$\Rightarrow \mathrm{p}^{2}=16$
$\Rightarrow \mathrm{p}=\pm \sqrt{16}$
$\Rightarrow \mathrm{p}=\pm 4$