TASK DEFINITION: Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.
PROBLEM: Context : HD 141937 is a star in the constellation of Libra at a distance of 109 ly.
Answer : Libra

SOLUTION: Which was the constellation for HD 141937?

PROBLEM: Context : Timelash is the fifth serial of the 22nd season in the British science fiction television series Doctor Who, which was first broadcast in two weekly parts from 9--16 March 1985.
Answer : Doctor Who

SOLUTION: What series is Timelash a part of?

PROBLEM: Context : The 2015 Singapore Grand Prix (formally known as the 2015 Formula 1 Singapore Airlines Singapore Grand Prix) was a Formula One motor race held on 20 September 2015 at the Marina Bay Street Circuit in Marina Bay, Singapore.
Answer : 20 September 2015

SOLUTION:
When did 2015 Singapore Grand Prix occur?