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.

Category: LITERARY OPERAS 
Clue: Operas based on this author's works include "Il Talismano", "Il Templario" & "La Prigione d'Edimburgo"
sir walter scott

Category: THE 1970s 
Clue: G. Gordon Liddy, E. Howard Hunt & Egil Krogh were nicknamed this because they "plugged leaks"
plumbers

Category: BRITISH ROYALTY 
Clue: After the death in combat of the previous king, he became the last one to win the crown while on the battlefield

henry vii

