Final answer:
The correct verb form to complete the sentence is 'miraron'
Step-by-step explanation:
The correct verb form that completes the sentence is miraron.
In Spanish, when referring to the past actions of a group of people (third person plural), we use the verb form miraron.
For example, if we say 'Ellos miraron la televisión ayer', it means 'They watched TV yesterday'.
Learn more about Spanish verb conjugation