$A$ molecule $(X)$ has $(i)$ four sigma bonds formed by the overlap of $sp^2$ and $s$ orbitals,(ii) one sigma bond formed by $sp^2$ and $sp^2$ orbitals,and (iii) one $\pi$ bond formed by $p_z$ and $p_z$ orbitals. Which of the following is $X$?

Which of the following overlaps is incorrect (assuming $Z$-axis is the internuclear axis)?
$(A)$ $2p_y + 2p_y \to \pi$-bond formation
$(B)$ $2p_x + 2p_x \to \sigma$-bond formation
$(C)$ $3d_{xy} + 3d_{xy} \to \pi$-bond formation
$(D)$ $2s + 2p_y \to \pi$-bond formation
$(E)$ $3d_{xy} + 3d_{xy} \to \delta$-bond formation
$(F)$ $2p_z + 2p_z \to \sigma$-bond formation

Which type of overlapping results in the formation of a $\pi$ bond?

The triple bond between two carbon atoms in ethyne is formed by.......

Select the molecule which has only one $\pi$-bond.

Which of the following molecules possesses a bond formed by $sp^2-sp$ orbital overlap?