This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Passage: When Pasternak stopped producing Durbin's pictures, and she outgrew her screen persona and pursued more dramatic roles, the studio signed 13-year-old Gloria Jean for her own series of Pasternak musicals from 1939; she went on to star with Bing Crosby, W. C. Fields, and Donald O'Connor. A popular Universal film of the late 1930s was Destry Rides Again (1939), starring James Stewart as Destry and Marlene Dietrich in her comeback role after leaving Paramount Studios.
What year did the studio sign Gloria Durbin?