I believe the answer is B
Answer:
gustaban
Explanation:
Because, gustaban ends in a -an, which means that it applies to the they/y'all because the subject is "your parents", being plural. And -an means that what it is talking about is plural.
We are five brothers. Ricardo, José Luis and Alejandro are (1). Francisco is (2). He is the husband of (3) older sister, Mercedes. Francisco is Argentine. (4) dads live in Mar del Plata. Vicente is the son of (5), Ricardo. He is (6) favorite nephew. (7) Mama is called Isabel and is Spanish. They live with (8) family in Seville. José Luis studies in Monterrey and lives with Aunt Remedios and (9) two children, Carlos and Raquel, (10) cousins. Alejandro and I live with (11) parents in Guadalajara. The dads of (12) mom also live with us. Alejandro and I share (13) problems with (14) our grandparents. They are very good. And you, how is (15) your family?