You will be given a definition of a task first, then some input of the task.
In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.

Context: He appeared at both the Hamburg State Opera and the Vienna State Opera in 1981 Link Information: To replace the aging wooden structure, the first stone was laid on 18 May 1826 for the Stadt-Theater on the present-day site of the Hamburg State Opera. The new theater, with seating for 2,800 guest, was inaugurated less than a year later Answer: Hamburg State Opera
Output:
Which of the two operas at which Schunk appeared in 1981 is older?