Given below are three schematic graphs of potential energy $V(r)$ versus distance $r$ for three atomic particles : electron $\left(e^{-}\right)$, proton $\left(p^{+}\right)$and neutron $(n)$, in the presence of a nucleus at the origin $O$. The radius of the nucleus is $r_0$. The scale on the $V$-axis may not be the same for all figures. The correct pairing of each graph with the corresponding atomic particle is
$(1, n),\left(2, p^{+}\right),\left(3, e^{-}\right)$
$\left(1, p^{+}\right),\left(2, e^{-}\right),(3, n)$
$\left(1, e^{-}\right),\left(2, p^{+}\right),(3, n)$
$\left(1, p^{+}\right),(2, n),\left(3, e^{-}\right)$
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