Which of the following contains a vague pronoun reference?
A. According to Katie, Willie Mays hit 660 career home runs, although Joe DiMaggio had a higher batting average. She said that he is her favorite player.
B. According to Katie, Willie Mays hit 660 career home runs, although Joe DiMaggio had a higher batting average. She said that Mays is her favorite player.
Select the correct answer from the given choices and respond with the letter of the chosen option.

A