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: a start walking from a place at a uniform speed of 4 kmph in a particular direction . after half an hour , b starts from the same place and walks in the same direction as a at a uniform speed and overtakes a after 1 hour 48 minutes . find the speed of b . 
Options: a ) 4.7 kmph , b ) 4.6 kmph , c ) 4 kmph , d ) 7 kmph , e ) 5.3 kmph
Example Output: b

Example Input: Problem: the sum of three consecutive even numbers is 63 . find the middle number of the three ? 
Options: a ) 14 , b ) 23 , c ) 25 , d ) 29 , e ) 21
Example Output: e

Example Input: Problem: a room of 6 m 20 cm long and 5 m 74 cm broad is to be paved with square tiles . find the least number of square tiles required to cover the floor . 
Options: a ) 88900 , b ) 87700 , c ) 88970 , d ) 88000 , e ) 89000
Example Output:
c