I am an undergraduate in physics and I am getting myself prepared for some research. I am taking a class which essentially gives me academic credit for a supervised research project I do under a faculty member. However, the choice of my research varies with contingent factors involved. For instance, my professor told me that I should really work on something I enjoy (like black holes, which involves general relativity), more than something that I can turn into serious published work (like globular clusters, which I could probably make better progress in). However, it is really important to me to also build an important academic profile and I think it would look good if I can work on a project that would evolve into professional research by the time I graduate. Not to say that if I did something on black holes now, I would have to abandon it as soon as I got a grade for the course. But what should I do? Any advice?