Which of the following statements is /are correct
(A) $C{H}_3^{+}$ shows $S{P}^2$ -hybridisation where as  $C{H}_3^{-}$ shows $S{P}^3$ hybridisation
(B) $N{H}_4^{+}$  has a rectangular tetrahedral geometry
(C) $S{P}^2$  - hybridized orbitals have equal  s and p character
(D) Hybridised orbitals always form  $\sigma$ bonds.

The correct answer is