instruction:
In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to write a question that clarifies the given question in such a way that the generated question has one unique answer.
question:
Who achieved a victory at the battle of marathon?
answer:
What country achieved a victory at the battle of marathon?


question:
Who does the voice of mcqueen in cars?
answer:
Who does the voice of Lightning McQueen in the Cars films?


question:
Who uses a signalling system known as tick tack?
answer:

Who in general uses a signalling system known as tick tack?