Final answer:
The verb 'soy' should be used to fill in the blank.
Step-by-step explanation:
The correct verb to fill in the blank is 'soy'. The sentence 'Yo soy chilena' translates to 'I am Chilean' in English. In Spanish, the verb 'ser' is used to indicate nationality or origin. In this case, 'soy' is the correct form of the verb for the subject 'yo' (I).
Learn more about Spanish verbs