What is the greatest debt owed by the Buddhist world to Sri Lanka

Q. What is the greatest debt owed by the Buddhist world to Sri Lanka?

(a) The preservation of Buddha’s relics and sacred Bodhi tree

(b) The reservation of the Pali canon in its entirety

(c) The development of Buddhism through Simhalese commentaries of Buddhist texts

(d) The propagation of Buddhism in South-East Asian countries

Ans: (d) The propagation of Buddhism in South-East Asian countries