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 length of the bridge , which a train 140 metres long and travelling at 45 km / hr can cross in 30 seconds , is ? 
Options: a ) 255 , b ) 267 , c ) 235 , d ) 277 , e ) 211
Example Output: c

Example Input: Problem: a boeing 757 flies a direct route from dallas , tx , to phoenix , az and then returns to dallas , tx . the flight is 900 miles one way . it took 2 hrs and 15 minutes for the flight to phoenix and 2 hrs for the flight back to dallas . what was the speed of the wind in mph ? 
Options: a ) 20 mph , b ) 25 mph , c ) 30 mph , d ) 35 mph , e ) 40 mph
Example Output: b

Example Input: Problem: a circular metal plate of even thickness has 12 holes of radius 1 cm drilled into it . as a result the plate lost 1 / 6 th its original weight . the radius of the circular plate is 
Options: ['a ) 16 sqrt 2', 'b ) 8 sqrt 2', 'c ) 32 sqrt 2', 'd ) sqrt 72', 'e ) sqrt 82']
Example Output:
d