Answer:
The Second one is true.
Explanation:
To solve this, you need to understand the basic rules of adding, multiplication, division, etc of square roots.
So, I just came up with examples, and solved.
![\sqrt[2]{3} *\sqrt[2]{7} \\eq \sqrt[4]{3*7}](https://img.qammunity.org/2021/formulas/mathematics/middle-school/x15lez3ueerbpigf7iloi4cjz9xy15ktv0.png)
No. This does no make sense. (according to the rules of square roots)

This makes sense because it is similar to the adding and subtracting variables with coefficients.
Third one is definitely not true. How can you divide something, and end up multiplying like that? No. Definitely not true.
Fourth one is not true, because the exponent would remain out of the square root. The Second one is true.
Hope this helps!