Final answer:
The correct verb to fill in the blank is "hicieron" which means "they did".
Step-by-step explanation:
The correct verb to fill in the blank in the given sentence is hicieron.
The subject of the sentence, "Alma y Sonia", is plural, so we need to use the third person plural form of the verb. The verb "hicieron" is the correct choice as it agrees with the subject and means "they did".
For example: "Alma y Sonia hicieron toda la tarea anoche, antes de acostarse." (Alma and Sonia did all the homework last night, before going to bed.)
Learn more about Spanish verbs