Hey there - I have been in the same position as you. As a student interested in both science and commerce, I wanted to take both chemistry and economics/business. After a bit of research and asking seniors, I decided to take chemistry and economics. Chemistry so far is tolerable - you simply have to be diligent with a good sense of work ethics. I decided to take economics over business since it foresees the bigger aspect in a country's point of view, and I am personally loving it! Business on the other hand comes down to organizations and specific strategies they use for example. In your case however, if you only can chose one between the three then make sure to see what interests you more and I'm sure you won't regret your decision. Good luck bud!