You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

[Q]: Category: HISTORIC EUROPEAN LEADERS 
Clue: On June 15, 1961 Walter Ulbricht assured journalists that "No one intends to build a wall" dividing this city
[A]: berlin


[Q]: Category: JORDAN 
Clue: Jordan lost the city of Jerusalem & the territory known as the West Bank during a war in this year
[A]: 1967


[Q]: Category: RELIGION 
Clue: This German's attacks on the Roman Catholic church began the Reformation
[A]:
martin luther