The correct answer is D. 1993.
Ranasinghe Premadasa was the President of Sri Lanka from 1989 to 1993. He was assassinated on May 1, 1993, by a suicide bomber while addressing a public rally in Colombo.
Option A, 1963, is incorrect because Ranasinghe Premadasa was not yet a politician in 1963. He was born in 1924 and entered politics in the early 1950s.
Option B, 1973, is incorrect because Ranasinghe Premadasa was not yet a member of the Sri Lankan government in 1973. He was elected to the Parliament of Sri Lanka in 1970, but he did not hold a ministerial position until 1977.
Option C, 1983, is incorrect because Ranasinghe Premadasa was not yet the President of Sri Lanka in 1983. He was elected President in 1988.
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