The Carbon-Carbon Sigma Bond in Ethane Is Formed by Overlap $2 p-2 p$

The carbon-carbon sigma bond in ethane is formed by overlap of which two orbitals?

A) $2 p-2 p$
B) $\mathrm{sp}-\mathrm{sp}$
C) $\mathrm{sp}^{2}-\mathrm{sp}^{2}$
D) $\mathrm{sp}^{3}-\mathrm{sp}^{3}$