Which of the following molecules are aromatic?

• A

  $\mathbf{M}, \mathbf{N}, \mathbf{O}$, and $\mathbf{P}$
• B

  $\mathbf{M}$ and $\mathbf{O}$ only
• Correct answer
  C

  $\mathbf{M}, \mathbf{N}$ and $\mathbf{O}$ only
• D

  $\mathbf{N}$ and $\mathbf{P}$ only

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