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: the speed of a car is 60 km in the first hour and 30 km in the second hour . what is the average speed of the car ? 
Options: a ) 45 kmph , b ) 65 kmph , c ) 75 kmph , d ) 85 kmph , e ) 90 kmph
Example Output: a

Example Input: Problem: the ratio between the length and the breadth of a rectangular park is 3 : 2 . if a man cycling along the boundary of the park at the speed of 12 km / hr completes one round in 8 minutes , then the area of the park ( in sq . m ) is 
Options: a ) 153200 , b ) 153400 , c ) 153600 , d ) 154000 , e ) 154200
Example Output: c

Example Input: Problem: can you find a 7 digit number which describes itself . the first digit is the number of zeros in the number . the second digit is the number of ones in the number , etc . for example , in the number 21200 , there are 2 zeros , 1 one , 2 twos , 0 threes and 0 fours . 
Options: a ) 4211000 , b ) 1211000 , c ) 5211000 , d ) 2211000 , e ) 3211000
Example Output:
e