Got a B in corporate finance...

nope. that B will ensure you never work in financial services

Obvious troll is obvious.

Game. Over.

well if you can't get an A in corp fin, I doubt you'll pass the IB interviews

You might have to retake it.

It's not going to matter if you can talk through the interview. Have examples of your strengths to show that a B doesn't matter.

In case this isn't a troll: most firms (including every IB role I've ever applied to) do not ask for a transcript or specific course grades during and interview so only your GPA which you list on your resume matters. They may end up checking during a background check but that's just to see that you didn't lie about your GPA or anything ->not to vet your specific grades.

Ya no way it matters in that no bank will be asking for your transcript...at least until after you have the job. However, there were a couple banks were I was asked point blank what finance/accounting classes I took and what my grades were in them. So, that could potentially end up being an awkward question if its asked. But, I don't think the B in the finance class directly hurting you is the issue. The more important issue is does that B in Finance indicate that your strengths may lie outside of banking. That's a much more difficult question that only you can really answer.

grade in specific class has no bearing what so ever on whether you can get a banking job or not

You are banned from the financial field with a B in corp fin per the Corporate Finance Standards Board (CFSB).

Good luck in marketing.