Who was/were the 10th century composer(s) of the Nalayira Divya Prabandham?

Q. Who was/were the 10th century composer(s) of the Nalayira Divya Prabandham? [CDS 2018]

A.            Alvars

B.            Nayanars

C.            Appar

D.            Sambandar

Answer: Alvars