Stream of consciousness rationale: The important part for answering this question is: Ranil Wickramasinghe has been sworn in as prime minister the most times in the country's history, on four separate occasions (May 1993, December 2001, January 2015 and August 2015), whilst Dudley Shelton Senanayaka and Sirimavo Bandaranayake were appointed three times.
The question and answer pair are described below.
Q: Ranil Wickramasinghe has been sworn in as prime minister the most times in the country's history, on four separate occasions (May 1993, December 2001, January 2015 and August 2015), whilst Dudley Shelton Senanayaka and Sirimavo Bandaranayake were appointed three times.

Answer this question based on the passage: who was the first sri lankan politician who held the office of the prime minister for four times?
A: Ranil Wickramasinghe