A certain junior class has 1,000 students and a certain senior class has 600 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 at will be a sibling pair?  Choose the correct answer:
A) 3/40,000	B) 1/10,000	C) 9/2,000	D) 1/60	E) 1/15
Total number of ways of choosing one student from each group is = 600 * 1000   Number of cases in which a sibling pair will be got is = 60   Thus the probability that the 2 students selected will be a sibling pair is   = 60 /(600 * 1000)   = 1/10,000   1/10,000
<result>B</result>
A certain junior class has 1,000 students and a certain senior class has 600 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 at will be a sibling pair?