Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

[Q]: Problem: last year elaine spent 20 % of her annual earnings on rent. this year she earned 20 % more than last year and she spent 30 % of her annual earnings on rent. the amount she spent on rent this year is what percent of the amount spent on rent last year ?
Options: a. 185.5, b. 180.0, c. 167.5, d. 172.5, e. 177.5
[A]: b


[Q]: Problem: virginia, adrienne, and dennis have taught history for a combined total of 96 years. if virginia has taught for 9 more years than adrienne and for 12 fewer years than dennis, for how many years has dennis taught ?
Options: a. 23, b. 32, c. 35, d. 41, e. 42
[A]: e


[Q]: Problem: how many figures are required for numbering the pages of a book containing 1000 pages ?
Options: a. 2726, b. 2878, c. 2893, d. 2765, e. 1811
[A]:
c