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

Example Input: Problem: what is the probability of getting a sum of 8 or 14 when rolling 3 dice simultaneously ? 
Options: a ) 1 / 6 , b ) 1 / 4 , c ) 1 / 2 , d ) 21 / 216 , e ) 32 / 216
Example Output: a

Example Input: Problem: in how many ways 4 boys and 2 girls can be seated in a row so that they are alternate . 
Options: a ) 48 , b ) 288 , c ) 12 , d ) 256 , e ) none
Example Output: a

Example Input: Problem: a box contains 20 electric bulbs , out of which 4 are defective . two bulbs are chosen at random form this box . the probability that at least one of these is defective is : 
Options: a ) 8 / 19 , b ) 7 / 19 , c ) 10 / 19 , d ) 20 / 19 , e ) 22 / 19
Example Output:
b