I would assume carpeta because it ends in a I’m not sure tho.
Your answer would be A. Novembre 8 because it means November 8th and November is the 11th month and it's not b because that says August 11th and not c because that means August 11th again.
Answer:
(A) A ellos les gusta estudiar en la biblioteca.
Y por eso le voy a explicar lo que pasa