A quick guide to Tharman Shanmugaratnam, Ng Kok Song, and Tan Kin Lian—experience, achievements, and what they stand for.Tharman ShanmugaratnamAge: 66Experience:Began as an economist at the Monetary Authority of Singapore (MAS) in 1982 and rose to managing director by 2001.Elected Member of Parliament (MP) in 2001.Held key ministerial roles, including Education Minister (2003–2008), Finance Minister …