Answer:
1.) not using a pronoun at all.
Step-by-step explanation:
Not using a pronoun is the right way to correct this ambiguity.
An ambiguous pronoun happens when a pronouns have an unclear antecedent, such that it's not clear who is referring to.
For example:
My cousin and his brother are about to take the bus, he's late to school and he has to meet his girlfriend. (In this case, the second pronoun is not clear, we don't who is referring to).
We can fix this ambiguity without using pronouns in the second time:
My cousin and his brother are about to take the bus, he's late to school and his brother has to meet his girlfriend.