In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: an employer pays rs . 20 for each day a worker works and for felts rs . 3 for each day is ideal at the end of sixty days a worker gets rs . 280 . for how many days did the worker remain ideal ? 
Options: a ) 10 , b ) 40 , c ) 30 , d ) 20 , e ) 50
Example Output: b

Example Input: Problem: a man swims downstream 76 km and upstream 48 km taking 4 hours each time ; what is the speed of the current ? 
Options: a ) 3 kmph , b ) 1.5 kmph , c ) 3.5 kmph , d ) 6.5 kmph , e ) 7 : 3 kmph
Example Output: c

Example Input: Problem: a runs 1 ¾ times as fast as b . if a gives b a start of 84 m , bow far must winning post be so that a and b might reach it at the same time ? 
Options: a ) 196 m , b ) 194 m , c ) 186 m , d ) 296 m , e ) 106 m
Example Output:
a