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: a pipe can fill a cistern in 33 minutes . find the time in which 1 / 11 part of the cistern will be filled ? 
Options: a ) 5 min , b ) 2 min , c ) 3 min , d ) 1 min , e ) 10 min
Example Output: c

Example Input: Problem: what is the minimum number of square tiles required to tile a floor of length 5 metres 78 cm and width 3 metres 74 cm ? 
Options: a ) 187 , b ) 180 , c ) 190 , d ) 195 , e ) 197
Example Output: a

Example Input: Problem: a can do a work in 7 days b in 12 days and c in 5 days . if they work on it together then in how many days required to complete the work ? 
Options: a ) 420 / 177 , b ) 420 / 179 , c ) 410 / 87 , d ) 90 / 14 , e ) 77 / 56
Example Output:
b