Explanation:

Alright, here’s what you need to know about those sections in the Hindu Minority and Guardianship Act:

- Section 7: This talks about who can act as a natural guardian of a minor after the death of one parent. It’s about natural guardians, not testamentary ones.

- Section 8: This deals with the powers of a natural guardian. Mainly, it covers what a guardian can or cannot do with the minor’s property. Again, about natural guardians.

- Section 9: This is the star section for testamentary guardians. It lays out who can appoint a testamentary guardian—that is, a guardian named in a will by the parents, and how all that works.

- Section 12: This is about not appointing a guardian for a minor married girl whose husband is alive, with a few exceptions.

So, your answer—option 3, Section 9—is the correct one for testamentary guardians.