Final answer:
The appropriate verb form is 'salga'.
Step-by-step explanation:
The appropriate verb form to fill in the blank in the given sentence is C. salga. The verb form 'salga' is the third person singular form of the verb 'salir' (to leave), and it agrees with the subject 'Ana'. In this context, it translates to 'Don't leave'.
Learn more about Verb forms in Spanish