Who wrote the book 'Hindutva: Who is a Hindu?'

Who wrote the book 'Hindutva: Who is a Hindu?'
(A) Vinayak Damodar Savarkar
(B) Madan Mohan Malviya
(C) Swami Dayanand Saraswati
(D) Balgangadhar Tilak

Answer: Vinayak Damodar Savarkar