The answer is A, Est-ce que tu fais quand le prof parle.
Mon père est fort (masculine singular as the noun "père")
ma sœur est forte (sœur feminine ----> forte)
Ils sont forts (ils = 3rd person masculine plural ----> forts)
elles sont fortes (elles = 3rd person feminine plural ------> fortes)
the adjectives , even after a verb , (adjectifs attributs du sujet ,in French) do have to agree in gender and plural or singular.
Hope I helped !!
They refuse the French Culture is your answer.
hope this helps!
