Replace "my mother's gift" with a pronoun. Which of the following is correct?

Using "her" to replace "my mother's gift" is correct because "her" is the appropriate pronoun that refers specifically to the feminine subject in this context. "My mother" indicates a female parent, thus when replacing it with a pronoun, "her" accurately reflects this gender.

The other options do not fit this context. "His" is a masculine pronoun that would refer to a male subject, which is not applicable here. "Their" is a plural pronoun that could refer to a group or be used as a singular gender-neutral pronoun, but it does not directly relate to "my mother." "Its" typically refers to non-human entities or objects, making it unsuitable to replace a mother's gift, which implies a level of human connection.