# Which is the only member of Group-15 p-block elements that does not exhibit allotropy?

$\begin{array}{1 1} Only\; Bismuth \\ Only \;Nitrogen \\ Nitrogen \;and\; Bismuth \\Anitomy \;and\; Arsenic \end{array}$

Except nitrogen and bismuth, all other elements of this group show allotropy.
Note: Solid nitrogen exists as $\alpha$-Nitrogen and $\beta$-Nitrogen,