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 edges of a cuboid are 4 cm , 4 cm and 6 cm . find the volume of the cuboid ?
Options: a ) 90 , b ) 60 , c ) 96 , d ) 80 , e ) 72
Example Output: c

Example Input: Problem: a boat takes 19 hours for travelling downstream fro poin a to point b and coming back to a point c midway between a and b . if the velocity of the stream is 4 kmph and the speed of the boat in still water is 14 kmph , what is the distance between a and b ?
Options: a ) 180 km , b ) 190 km , c ) 220 km , d ) 230 km , e ) none
Example Output: a

Example Input: Problem: a tank is 25 m long 12 m wide and 6 m deep . the cost of plastering its walls and bottom at 75 paise per sq m is
Options: a ) rs . 258 , b ) rs . 358 , c ) rs . 458 , d ) rs . 558 , e ) none of these
Example Output:
d