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: the average of 11 10 prime numbers which are odd is ?
Options: a. 17.72, b. 18.52, c. 19.63, d. 16.53, e. 15.63

A: a
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Q: Problem: how much is 60 % of 40 is greater than 4 / 5 of 30 ?
Options: a. 8, b. 3, c. 7, d. 0, e. 1

A: d
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Q: Problem: a cycle is bought for rs. 900 and sold for rs. 1170, find the gain percent ?
Options: a. 27 %, b. 20 %, c. 80 %, d. 30 %, e. 24 %

A:
d
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