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.

[EX Q]: Category: THE "I"s HAVE IT 
Clue: In a proverb, it's "no excuse" for breaking the law
[EX A]: ignorance

[EX Q]: Category: RULERS 
Clue: In 770 this king of the Franks married Desiderata, daughter of the Lombard king Desiderius
[EX A]: charlemagne

[EX Q]: Category: MEN OF SCIENCE 
Clue: On a scale of 1 to 10, his "Earthquakes" article for the 15th edition of Encyclopedia Britannica was a 10
[EX A]:
richter