Fill in the blank (_) in the following sentence from the following choices.
Sentence: Katrina cooked a chicken for Mary, since _ knew how to cook a chicken quite well.

Choice 1: Katrina cooked a chicken for Mary, since Katrina knew how to cook a chicken quite well.
Choice 2: Katrina cooked a chicken for Mary, since Mary knew how to cook a chicken quite well.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
1
1.