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: an optometrist charges $ 150 per pair for soft contact lenses and $ 85 per pair for hard contact lenses. last week she sold 5 more pairs of soft lenses than hard lenses. if her total sales for pairs of contact lenses last week were $ 1,220, what was the total number of pairs of contact lenses that she sold ?
Options: a. 9, b. 13, c. 15, d. 17, e. 19

A: a
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Q: Problem: what least number should be added to 1057, so that the sum is completely divisible by 23
Options: a. a. 4, b. b. 1, c. c. 2, d. d. 3, e. e. 5

A: b
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Q: Problem: on june 1 a bicycle dealer noted that the number of bicycles in stock had decreased by 3 for each of the past 5 months. if the stock continues to decrease at the same rate for the rest of the year, how many fewer bicycles will be in stock on september 1 than were in stock on january 1 ?
Options: a. 8, b. 12, c. 24, d. 32, e. 36

A:
c
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