Final answer:
The correct verb form is 'hice'
Step-by-step explanation:
The correct verb form to fill in the blank in the sentence would be hice. The sentence is asking 'I did everything possible to help Ana.' The verb 'hice' is the first person singular past tense form of the verb 'hacer' (to do/make) in Spanish. It is used to describe an action that the speaker did in the past.
Learn more about Verb forms in Spanish