I am also B.Com graduate and I have been working as SD consultant from last 5 years. With your degree you can go for any functional module. SD FI MM are best possible combination but I have seen people who have B.Com or MBA degree but they are working as PP PM or even BI/BO consultans. Its all depends on your personal interest and your area of expertise. In most of the cases degree has nothing to do with module selection in my point of view.