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: KIDDY LIT 
Clue: The wedding meal eaten by this odd Edward Lear pair is "mince and slices of quince"

SOLUTION: the owl and the pussycat

PROBLEM: Category: SCIENCE & NATURE 
Clue: Developed by astronomer A.E. Douglass, dendrochronology determines age in this way

SOLUTION: counting tree rings

PROBLEM: Category: WHAT'S THE ALTERNATIVE? 
Clue: Autosuggestion ("I am great, great") is classified as a form of "self" this ("I am getting sleepy, sleepy")

SOLUTION:
self-hypnosis