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 Input:
Problem: the length of a rectangular floor is more than its breadth by 100 %. if rs. 600 is required to paint the floor at the rate of rs. 3 per sq m, then what would be the length of the floor ?
Options: a. 15.0 m., b. 14.4 m., c. 12.0 m., d. 16.2 m., e. 16.5 m.

Ex Output:
b


Ex Input:
Problem: if julie rows 32 km upstream and 72 km down steam taking 4 hours each, then the speed of the stream
Options: a. 1.5 kmph, b. 0.5 kmph, c. 0.4 kmph, d. 1.6 kmph, e. 2.5 kmph

Ex Output:
b


Ex Input:
Problem: susan made a block with small cubes of 5 cubic cm volume to make a block 7 small cubes long, 7 small cubes wide and 6 small cubes deep. she realise that she has used more small cubes than she really needed. she realised that she could have glued a fewer number of cubes together ot look like a block with same dimensions, if it were made
Options: ['a. 194', 'b. 195', 'c. 196', 'd. 197', 'e. 198']

Ex Output:

a