You need to take the most challenging courseload your school offers…but also one where you will get top grades. Acceptances to BS/MD programs are as competitive or MORE competitive than acceptances to elite colleges…so think about that as you plan your courses.
But also, if you are applying BS/MD, you need to look at the other things you should be doing to convince these programs you know what being a doctor really takes…and means.
I’ll let the experts on these programs comment.