You will be given a definition of a task first, then some input of the task.
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.

Context : Once Upon a Song (Chinese: 201314), is a 2015 musical drama television series produced by Hong Kong Television Network.
Answer : Hong Kong Television Network
Output:
What studio produced Once Upon a Song?