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.

Problem: if a ' s height is 40 % less than that of b, how much percent b ' s height is more than that of a ?
Options: a. 66.66 %, b. 66.68 %, c. 66.766 %, d. 86.66 %, e. 66.65 %
a

Problem: 30 pens and 75 pencils were purchased for 750. if the average price of a pencil was 2.00, find the average price of a pen.
Options: a. 20, b. 11, c. 12, d. 13, e. 14
a

Problem: jane and thomas are among the 8 people from which a committee of 4 people is to be selected. how many different possible committees of 4 people can be selected from these 8 people if at least one of either jane or thomas is to be selected ?
Options: a. 28, b. 46, c. 55, d. 63, e. 70

c