Which of the following contains a vague pronoun reference?

 - Before Ken decided on a double major in history and Russian literature, he talked to them about the requirements for each major.
 - Before Ken decided on a double major in history and Russian literature, he talked to academic advisers about the requirements for each major.
The first answer choice contains a vague pronoun reference. The pronoun them is used without its antecedent.
The second answer choice shows a possible correction for the vague pronoun reference. Them has been replaced with academic advisers.
Before Ken decided on a double major in history and Russian literature, he talked to academic advisers about the requirements for each major.