Answer: option c
Explanation:
By definition, if you have:
![\sqrt[n]{x}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4jd4hhgr7sno98iogywzuhv1ml0kvt7xry.png)
you can rewrite it has following:

Therefore, keeping the above on mind, you can rewrite the expression given in the problem, as you can see below:
![15x^{(1)/(3)}y^{(1)/(5)}=(15\sqrt[3]{x})(\sqrt[5]{y})](https://img.qammunity.org/2020/formulas/mathematics/middle-school/n7gsk52ofnvnsds10n5bsxwakn1i4fpdad.png)
Both terms are multiples of 15, then take the 15th root of both and multiply the exponents by 15. Therefore you obtain:
![15\sqrt[15]{x^5y^3}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/t32epkdpmv2casbiqhivl55qnesyv4jc1n.png)