The $\mathrm{C}-\mathrm{H}$ bond and $\mathrm{C}-\mathrm{C}$ bond in ethane are formed by which of the following types of overlap?

• A

  $s \mathrm{p}^{2}-s$ and $s \mathrm{p}^{2}-s \mathrm{p}^{2}$
• B

  $s p-s$ and $s p-s p$
• C

  $p-s$ and $p-p$
• Correct answer
  D

  $s p^{3}-s$ and $s p^{3}-s p^{3}$

Hence, the correct answer is option: 'D'.