You will be given a definition of a task first, then some input of the task.
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 consistency, answers should be in all lower cased letters.

Category: THE 1860s 
Clue: In 1868 this Liberal Party member succeeded Disraeli as British Prime Minister; he served in that capacity 3 other times
Output:
gladstone