Fill in the blank (_) in the following sentence from the following choices.
Sentence: When Cynthia messed up his research, Megan giggled, so the professor gave _ a stern look.

Choice 1: When Cynthia messed up his research, Megan giggled, so the professor gave Cynthia a stern look.
Choice 2: When Cynthia messed up his research, Megan giggled, so the professor gave Megan a stern look.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
2
1.