None of the options make sense
Diseases that are inherited, like marcan syndrome are ...caused by genes
The answer is B. estudiante.
The article preceding it, 'las', is the plural feminine article. 'estudiante' in the sentence is singular only, but it is gender neutral. 'son' is the third person plural conjugation of the verb 'ser'. 'inteligentes' is an adjective that would refer to plural subjects. To fix the sentence, change 'estudiante' to 'estudiantes'.
Cierto
I think it says: Vieques has clean beaches.
Leo
Venden
Bebes
Creemos
Corre
Aprenden
Cómo
Debemos
