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: The Sangoma is a traditional diviner chosen by the ancestors of that particular family. The training of the Sangoma is called "kwetfwasa". At the end of the training, a graduation ceremony takes place where all the local sangoma come together for feasting and dancing. The diviner is consulted for various reasons, such the cause of sickness or even death. His diagnosis is based on "kubhula", a process of communication, through trance, with the natural superpowers. The Inyanga (a medical and pharmaceutical specialist in western terms) possesses the bone throwing skill ("kushaya ematsambo") used to determine the cause of the sickness.
Who is chosen by their chiefdom?