In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to provide one question which clarifies the input question and it has one unique answer, and also provide an answer to the generated question. Generated question and answer should be separated with a new line.
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Question: What led to the end of indus valley civilization?

Answer: According to Sir Mortimer Wheeler in 1953, what led to the end of indus valley civilization? 
 "Aryan invasion"


Question: When does the new magic the gathering set come out?

Answer: When does the new magic the gathering set come out broadly in 2015? 
 July 17, 2015


Question: Who has the most subscribers on youtube ever?

Answer:
Which channel has the most subscribers on youtube ever as of Dec 23, 2013? 
 PewDiePie