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.

[Q]: Category: NUN SENSE 
Clue: This 6th century Irish nun is also known as St. Bride, though she refused to marry
[A]: st. bridget


[Q]: Category: A LITTLE OF THE BUBBLY 
Clue: Roy Allen opened root beer stands in 1922 & introduced this brand name for his product
[A]: a&w


[Q]: Category: TIME 
Clue: Quick, it's the term for 1 billionth of a second
[A]:
a nanosecond