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

[EX Q]: Problem: from a group of 3 boys and 3 girls , 4 children are to be randomly selected . what is the probability that equal numbers of boys and girls will be selected ? 
Options: a ) 1 / 10 , b ) 4 / 9 , c ) 1 / 2 , d ) 3 / 5 , e ) 2 / 3
[EX A]: d

[EX Q]: Problem: in how many ways 3 boys and 3 girls can be seated in a row so that they are alternate . 
Options: a ) 144 , b ) 288 , c ) 36 , d ) 256 , e ) none
[EX A]: c

[EX Q]: Problem: a certain junior class has 1000 students and a certain senior class has 800 students . among these students , there are 60 siblings pairs each consisting of 1 junior and 1 senior . if 1 student is to be selected at random from each class , what is the probability that the 2 students selected will be a sibling pair ? 
Options: a ) 3 / 40000 , b ) 1 / 3600 , c ) 9 / 2000 , d ) 1 / 60 , e ) 1 / 15
[EX A]:
a