The pair of electrons in the given carbanion,${\mathrm{CH}}_3\mathrm{C}\equiv {\mathrm{C}}^{-}$, is present in which of the following orbitals?

• A

  ${\mathrm{sp}}^2$

• B

  $\mathrm{sp}$

• C

  $2\mathrm{p}$

• D

  ${\mathrm{sp}}^3$