Research Tracks Include:
Computer and Network Security
Network and Distributed Systems
Machine Learning and Computer Vision
Data Mining
Mobile Computing
What do you mean by “research tracks”? Do you mean major? Are you a high school or college student? I don’t see a “best” on the list – all are fields that could be interesting.
I assume these are mini-concentrations within a CS degree, or something like that. If so, I agree there is no “best”, it really depends upon what interests you. Each would take you in somewhat different directions. All have some value in the marketplace, although data mining and mobile computing may be a little more trendy right now.
When you get more acquainted with the department, you might find that the profs in some of these specialties have better connections for internships, etc., or are more connected with current needs in the profession. That info might help inform your choice.
Pick the one that interests you the most. Otherwise, machine learning and computer vision is the current hot fad.
I think that data mining has kinda’ morphed into machine learning these days.