Who wrote the book "Buddha Charitam"?

The correct answer is Option (3) → Ashwaghosh

The Buddhacharita (“Acts of the Buddha”) is a Sanskrit epic poem on the life of Gautama Buddha, written by Ashvaghosha in about the 1^st–2^nd century CE. Ashvaghosha, a Buddhist poet and philosopher, is linked by tradition with the court of the Kushana king Kanishka.