If $A=\{4 n+2 \mid n$ is a natural number $\}$ and $B=\{3 n \mid n$ is a natural number $\}$. Which of the following is correct for $A \cap B$ ?
- $\left\{12 n^{2}+6 n \mid n\right.$ is a natural number $\}$
- $\{24 \mathrm{n}-12 \mid \mathrm{n}$ is a natural number $\}$
- $\{60 \mathrm{n}+30 \mid \mathrm{n}$ is a natural number $\}$
- $\{12 \mathrm{n}-6 \mid \mathrm{n}$ is a natural number $\}$