quizzer       
noun [ C ] UK uk/ˈkwɪz.ər/ us/ˈkwɪz.ɚ/
 问答比赛参与者,智力竞赛参与者
someone who takes part in quizzes (= games in which you answer questions)
  I've been an avid quizzer for years. 这么多年来我一直都是个狂热的问答比赛参与者。 
 They were soon chased out of the pub by quizzers hunting spare stools. 他们很快就被寻找备用凳子的问答比赛参与者赶出了酒吧。 
 - More examples
 - "Who Wants to Be A Millonaire" was the big target for serious quizzers.
 - The documentary enters the world of professional quizzers and follows the UK's finest to the European Championships in Paris.
 - Mark now plays pub quizzes three or four times a week and is a regular on the serious quizzers circuit.