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.

[EX Q]: Problem: he average of 10 numbers is 23. if each number is increased by 4, what will the new average be ?
Options: a. 26, b. 27, c. 88, d. 99, e. 12
[EX A]: b

[EX Q]: Problem: find the curved surface area, if the radius of a cone is 35 m and slant height is 30 m ?
Options: a. 1100, b. 2200, c. 3300, d. 4400, e. 5500
[EX A]: c

[EX Q]: Problem: in a certain parking lot, 4 % of the cars are towed for parking illegally. however 80 % of the cars which are parked illegally are not towed. what percentage of cars in the parking lot are parked illegally ?
Options: a. 20 %, b. 25 %, c. 30 %, d. 35 %, e. 40 %
[EX A]:
a