All are wrong. Say "certain" or "a certainty". "Sure" is not a synonym for "certain". "Certain" means "known for sure". You can, however, say "I am sure our team will win". You can also say "It is a sure thing that our team will win". "Sure thing" is a colloquialism that means something certain to happen.

B definitely doesn't work at all. For "surely" to work you would a predicate nominative or predicate adjective after it, not a clause. Both A and C can work grammatically, but the whole structure sounds stilted and unnecessarily formal. It certainly doesn't sound like anything a sports fan would ever say in real life.

A