In this task, you need to provide the correct option for a given problem on probability from the provided options.

Ex Input:
Problem: two unbiased coins are tossed . what is the probability of getting two heads ? 
Options: a ) 1 / 2 , b ) 1 / 4 , c ) 2 / 3 , d ) 1 / 5 , e ) 2 / 7

Ex Output:
b


Ex Input:
Problem: it takes 60 identical printing machines 4 hours to print 200,000 cards . how long would it take 50 of these machines to print the same total ? 
Options: a ) 10 hr , b ) 5 hr , c ) 6 hr , d ) 4 hr 30 min , e ) 5 hr 12 min

Ex Output:
e


Ex Input:
Problem: if a card is drawn from a well shuffled deck of cards , what is the probability of drawing a black card or a face card ? 
Options: a ) 7 / 13 , b ) 15 / 26 , c ) 9 / 12 , d ) 8 / 13 , e ) 29 / 52

Ex Output:

d