The terms containing $x^r y^s$ (for certain $r$ and $s$ ) are present in both the expansions of $\left(x+y^2\right)^{13}$ and $\left(x^2+y\right)^{14}$. If $\alpha$ is the number of such terms, then the sum $\alpha \underset{\mathrm{r}, \mathrm{s}}{\sum}(\mathrm{r}+\mathrm{s})=$

• A

  27
• B

  40
• Correct answer
  C

  18
• D

  35

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