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: how many seconds will a train 250 meters long take to cross a platform 200 meters long if the speed of the train is 90 kmph ? 
Options: a ) 18 sec , b ) 15 sec , c ) 21 sec , d ) 16 sec , e ) 20 sec

Ex Output:
a


Ex Input:
Problem: ram , who is half as efficient as krish , will take 24 days to complete a task if he worked alone . if ram and krish worked together , how long will they take to complete the task ? 
Options: a ) 16 days , b ) 12 days , c ) 8 days , d ) 6 days , e ) 18 days

Ex Output:
c


Ex Input:
Problem: wilson can eat 25 marshmallows is 20 minutes . dylan can eat 25 in one hour . in how much time will the two eat 150 marshmallows ? 
Options: a ) 40 minutes . , b ) 1 hour and 30 minutes . , c ) 1 hour . , d ) 1 hour and 40 minutes . , e ) 2 hours and 15 minutes .

Ex Output:

c