In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

The medical term for a superficial loss of skin as would occur by scratching is?
abrasion

Show me the cast of bonnie and clyde?
Warren Beatty, Faye Dunaway, Michael J. Pollard, Gene Hackman, Estelle Parsons, Denver Pyle, Dub Taylor, Gene Wilder, Evans Evans, and Mabel Cavitt

What is the main source of heat and light energy?

Sun