You will be given a definition of a task first, then some input of the task.
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 city has a unique status in Brazil, as it is an administrative division rather than a legal municipality like other cities in Brazil. The name 'Brasilia' is commonly used as a synonym for the Federal District through synecdoche; However, the Federal District is composed of 31 administrative regions, only one of which is Brasilia proper, with a population of 209,926 in a 2011 survey; Demographic publications generally do not make this distinction and list the population of Brasilia as synonymous with the population of the Federal District, considering the whole of it as its metropolitan area. The city was one of the main host cities of the 2014 FIFA World Cup. Additionally, Brasilia hosted the 2013 FIFA Confederations Cup.
Output:
What did Brasilia host in 2011?