You are the owner of a Driving School. After a long day of driving, the instructors and students gather at the campus park for a picnic. The students grab their brown bags and gravitate without assignment to other students with similar driving school results in various areas of the park to each their lunch and discuss their progress. It is interesting that students who prefer Coke are together, those who like Orange are under the tree, and those who prefer Pepsi are on the bench. This is an example of: Blind study Cluster analysis Decision tree Simulation