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: if a train , travelling at a speed of 180 kmph , crosses a pole in 5 sec , then the length of train is ? 
Options: a ) 250 m , b ) 112 m , c ) 117 m , d ) 125 m , e ) 123 m
Example Output: a

Example Input: Problem: in a garden , there are 10 rows and 12 columns of mango trees . the distance between the two trees is 2 metres and a distance of one metre is left from all sides of the boundary of the garden . the length of the garden is ? 
Options: a ) 12 , b ) 27 , c ) 24 , d ) 29 , e ) 11
Example Output: c

Example Input: Problem: a tree of height 36 m is on one edge of a road broke at a certain height . it fell in such a way that the top of the tree touches the other edge of the road . if the breadth of the road is 12 m , then what is the height at which the tree broke ? 
Options: a ) 16 , b ) 17 , c ) 18 , d ) 19 , e ) 20
Example Output:
a