TASK DEFINITION: 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.
PROBLEM: Who's the best selling artist of all time?

SOLUTION: The Beatles

PROBLEM: Who abducted helen and led her to troy?

SOLUTION: Paris of Troy

PROBLEM: What are the 5 main characteristics of a mineral?

SOLUTION:
Formed by a natural process, Stable or metastable at room temperature, Represented by a chemical formula, Ordered atomic arrangement, and Usually abiogenic