Answer:
Intensive pronoun.
Step-by-step explanation:
An intensive pronoun is a pronoun that is used to emphasize the antecedent. Intensive pronouns end with "-self" or "-selves".
In the given sentence, Mariko is the subject while "herself" is the pronoun.
Considering the pronoun emphasizes the subject "Mariko", it acts as an intensive pronoun, as it emphasizes its antecedent.
Thus, the correct answer is an intensive pronoun.