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 teena is driving at 55 miles per hour and is currently 7.5 miles behind loe , who is driving at 40 miles per hour in the same direction then in how many minutes will teena be 15 miles ahead of loe ? 
Options: a ) 15 , b ) 60 , c ) 75 , d ) 90 , e ) 105
Example Output: d

Example Input: Problem: a garrison of 2000 men has provisions for 54 days . at the end of 15 days , a reinforcement arrives , and it is now found that the provisions will last only for 30 days more . what is the reinforcement ? 
Options: a ) 1800 men , b ) 3900 men , c ) 600 men , d ) 3800 men , e ) 900 men
Example Output: c

Example Input: Problem: two trains are running in opposite directions in the same speed . the length of each train is 120 meter . if they cross each other in 8 seconds , the speed of each train ( in km / hr ) is 
Options: a ) 42 , b ) 36 , c ) 28 , d ) 20 , e ) 54
Example Output:
e