Accounting or Business Administration to get into IB?

I'm currently applying to National University of Singapore(NUS) and Singapore Management University(SMU), but I'm caught between which course to take: Accounting or Business?

My concerns regarding the two courses:
Accounting - I can't see myself performing well ( meaning>3.7/4), especially because test grades can jump easily from A to C with a slight error in deducing my answer. But this degree has many job prospects. In my opinion, I feel like i'm taking a risk going into accounting and trying to secure a high GPA.

Business - I believe I can do well here possibly >3.7/4. But I'm unsure about the job prospects of this degree if I don't make it to IB (Any advice on the job prospects?)

I would be grateful if anyone could shed some light on which I should pick if I want to be an investment banker?

Thanks!