Answer:
When the verb is reflexive
Explanation:
You put the pronoun (yo,tu,el, ect.), then the me,te,se,nos,os(vosotros), or se and then the verb
Sophie y Charlie estan <em><u>trabajando</u></em> en una finca de café.
Hope it helps! :)
I think the answer is C. estaban
(you're welcome if this helped, Brainliest would be appreciated)
A usted because its formal.