Fill in the blank (_) in the following sentence from the following choices.
Sentence: Erin asked Sarah to be her agent, since _ was knowledgeable of the ins and outs of the music business.

Choice 1: Erin asked Sarah to be her agent, since Erin was knowledgeable of the ins and outs of the music business.
Choice 2: Erin asked Sarah to be her agent, since Sarah was knowledgeable of the ins and outs of the music business.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
2
2.