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

Example Input: Problem: if two dice are thrown together , the probability of getting a doublet on the dice is 
Options: a ) 1 / 6 , b ) 1 / 5 , c ) 1 / 4 , d ) 1 / 3 , e ) 1 / 2
Example Output: a

Example Input: Problem: there are 10 books on a shelf , of which 4 are paperbacks and 6 are hardbacks . how many possible selections of 5 books from the shelf contain at least one paperback and at least one hardback ? 
Options: a ) 75 , b ) 120 , c ) 210 , d ) 246 , e ) 252
Example Output: d

Example Input: Problem: there is a 75 % chance that tigers will not win at all during the whole season . there is a 25 % chance that germany will not play at all in the whole season . what is the greatest possible probability that the tigers will win and germany will play during the season ? 
Options: a ) 55 % , b ) 60 % , c ) 70 % , d ) 75 % , e ) 80 %
Example Output:
d