Let $S(n)=\frac{1}{n^4} \sum_{l=1}^n(l+2)(l+4)(l+6)$. The value of $\lim _{n \rightarrow \infty} S(n)$ is

• A

  $\frac{1}{6}$
• B

  $\frac{1}{2}$
• Correct answer
  C

  $\frac{1}{4}$
• D

  $1$

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