TASK DEFINITION: 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.
PROBLEM: Category: THE WINTER PALACE 
Clue: In 1881 the "Czar Liberator", the II czar of this name, asked to be taken to the palace to die after being fatally wounded

SOLUTION: alexander ii

PROBLEM: Category: EARLY ART 
Clue: This art form of setting stones or glass into mortar was the main decorative art of the Byzantine Empire

SOLUTION: mosaic

PROBLEM: Category: THE "G"-8 
Clue: It's a list of defined terms in a special subject at the end of a book

SOLUTION:
glossary