Fill in the blank (_) in the following sentence from the following choices.
Sentence: Katrina showed their large aquarium to Cynthia since _ had owned one for a long time.

Choice 1: Katrina showed their large aquarium to Cynthia since Katrina had owned one for a long time.
Choice 2: Katrina showed their large aquarium to Cynthia since Cynthia had owned one for a long time.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
1
1.