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: if a train , travelling at a speed of 360 kmph , crosses a pole in 5 sec , then the length of train is ?
Options: a ) 381 m , b ) 112 m , c ) 500 m , d ) 125 m , e ) 433 m
Example Output: c

Example Input: Problem: two buses each 3125 m long are running in opposite directions on parallel roads . their speeds are 40 km / hr and 35 km / hr respectively . find the time taken by the slower bus to pass the driver of the faster one ?
Options: a ) 50 sec , b ) 66 sec , c ) 48 sec , d ) 55 sec , e ) 45 sec
Example Output: a

Example Input: Problem: steve traveled the first 2 hours of his journey at 40 mph and the last 2 hours of his journey at 80 mph . what is his average speed of travel for the entire journey ?
Options: a ) 53.33 mph , b ) 56.67 mph , c ) 60 mph , d ) 64 mph , e ) 66.67 mph
Example Output:
c