Which pair of overlapping can not form covalent bond simultaneously between two atoms ?

• A

  $\text{ If }{\mathrm{p}}_{\mathrm{y}}+{\mathrm{p}}_{\mathrm{y}}\Rightarrow \mathrm{\sigma }\text{-bond, then }{\mathrm{p}}_{\mathrm{x}}+{\mathrm{p}}_{\mathrm{x}}\Rightarrow \mathrm{\pi }\text{-bond }$

• B

  $\text{ If }{\mathrm{p}}_{\mathrm{z}}+{\mathrm{p}}_{\mathrm{z}}\Rightarrow \mathrm{\sigma }\text{-bond, then }{\mathrm{d}}_{\mathrm{xy}}+{\mathrm{d}}_{\mathrm{xy}}\Rightarrow \mathrm{\pi }\text{-bond }$

• C

  $\text{ If }{\mathrm{p}}_{\mathrm{y}}+{\mathrm{p}}_{\mathrm{y}}\Rightarrow \mathrm{\pi }\text{-bond, then }{\mathrm{d}}_{\mathrm{xz}}+{\mathrm{d}}_{\mathrm{xz}}\Rightarrow \mathrm{\pi }\text{-bond }$

• D

  $\text{ If }{\mathrm{d}}_{{\mathrm{x}}^2-{\mathrm{y}}^2}+{\mathrm{d}}_{{\mathrm{x}}^2-{\mathrm{y}}^2}\Rightarrow \mathrm{\sigma }\text{-bond, then }{\mathrm{d}}_{\mathrm{xz}}+{\mathrm{d}}_{\mathrm{xz}}\Rightarrow \mathrm{\pi }\text{-bond }$