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

[EX Q]: Problem: if 4 people are selected from a group of 8 married couples , what is the probability that none of them would be married to each other ? 
Options: a ) 1 / 33 , b ) 2 / 33 , c ) 8 / 13 , d ) 16 / 33 , e ) 11 / 12
[EX A]: c

[EX Q]: Problem: how many cubes of 3 cm edge can be cut out of a cube of 18 cm edge 
Options: a ) 36 , b ) 232 , c ) 216 , d ) 455 , e ) 363
[EX A]: c

[EX Q]: Problem: 8 coins are tossed . whats is the probability that one and only one turns up head ? 
Options: a ) 1 / 256 , b ) 1 / 32 , c ) 1 / 64 , d ) 1 / 128 , e ) 1 / 189
[EX A]:
b