Fill in the blank (_) in the following sentence from the following choices.
Sentence: The man cut the nail of the dog, but not its hair, so the _ must have been short.

Choice 1: The man cut the nail of the dog, but not its hair, so the nail must have been short.
Choice 2: The man cut the nail of the dog, but not its hair, so the hair must have been short.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
2
1.