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 man can row a boat at 10 kmph in still water and the speed of the stream is 8 kmph . what is then time taken to row a distance of 90 km down the stream ? 
Options: a ) 8 hrs , b ) 5 hrs , c ) 15 hrs , d ) 15 hrs , e ) 20 hrs
Example Output: b

Example Input: Problem: find the length of the longest pole that can be placed in an indoor stadium 24 m long , 18 m wide and 16 m high 
Options: a ) 31 , b ) 32 , c ) 33 , d ) 34 , e ) 35
Example Output: d

Example Input: Problem: at 3 : 40 , the hour hand and the minute hand of a clock form an angle of : 
Options: a ) 130 , b ) 125 , c ) 140 , d ) 154 , e ) 145
Example Output:
a