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: a batsman makes a score of 87 runs in the 17 th inning and thus increases his average by 3. find his average after 17 th inning.
Options: a. 39, b. 88, c. 26, d. 87, e. 11

A: a
****
Q: Problem: a clock shows the time as 9 a. m. if the minute hand gains 7 minutes every hour, how many minutes will the clock gain by 6 p. m. ?
Options: a. 30 min, b. 35 min, c. 63 min, d. 50 min, e. 55 min

A: c
****
Q: Problem: in the figure given below, abc and cde are two identical semi - circles of radius 2 units. b and d are the mid points of the arc abc and cde respectively. what is the area of the shaded region ?
Options: ['a. 4 π - 1', 'b. 3 π - 1', 'c. 2 π - 4', 'd. ½ ( 3 π - 1 )', 'e. 2 π - 2']

A:
c
****