Final answer:
The word 'están mirando' is the correct choice to complete the sentence. It means 'are watching' in English.
Step-by-step explanation:
The correct word to complete the sentence is están mirando. In Spanish, the word 'están' is the third person plural form of the verb 'estar,' which means 'to be.' The subject 'Mis padres' is plural, so we use 'están' to match the subject. 'Mirando' is the present participle of the verb 'mirar,' which means 'to watch.' So the sentence translates to 'My parents are watching television.'
Learn more about Spanish Verbs