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'.

Ex Input:
Problem: what is the least number of square tiles required to pave the floor of a room 11 m 50 cm long and 1 m 50 cm broad ? 
Options: a ) 724 , b ) 804 , c ) 69 , d ) 844 , e ) none

Ex Output:
c


Ex Input:
Problem: town m town n town o town p town q town r ; town a town b town c town d town e town f in the table above , what is the least number of table entries that are needed to show the mileage between each town and each of the other 5 towns ? 
Options: a ) 11 , b ) 12 , c ) 13 , d ) 14 , e ) 15

Ex Output:
e


Ex Input:
Problem: 300 meter long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds . what is the length of the platform ? 
Options: a ) 388 , b ) 266 , c ) 350 , d ) 112 , e ) 134

Ex Output:

c