You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: DEMOGRAPHICS 
Clue: In 2005 the World Health Organization appropriately decided to stop hiring people who do this
smoke

Category: PLAYWRIGHTS 
Clue: This Brit won Tonys for Best Play in 1968, 1976, 1984 & 2007; in the '90s he settled for the 1998 Best Screenplay Oscar
tom stoppard

Category: MODERN U.S. HISTORY 
Clue: This group consisted of the Chief Justice, 4 members of Congress, & ex-heads of the CIA & the World Bank

the warren commission