Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Kronos (or Cronus) was the Greek equivalent of which Roman god?
cronus

Which English classic horse race for 3 year olds held at Doncaster every September began in 1776?
doncaster racecourse

What is the title of the play by Arthur Miller set around the Salem Witch trials of 1692?

arthur miller