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: ANIMAL VERBS 
Clue: Nag or pester persistently
badger

Category: NONFICTION 
Clue: While in prison Eldridge Cleaver wrote this 1968 book on the problems confronting black Americans
"soul on ice"

Category: WHAT THE "L" IS IT? 
Clue: They're tart red berries traditionally served in Sweden with thin pancakes

lingonberries