in case vs provided

[zahari]

hello everybody !!!!

I'd like you to help me with the following sentence:

Call me_____________ there's an emergency.

a. in the case
b. provided

The teacher's book gives (a) as the correct answer. Is (a) possible?? provided does not seem appropriate to me.However, i thought there is no such expression like in the case .I've seen it only followed by of (e.g.in the case of emergency). Then i thought that it may be a printer's error.Now i'm confused!

Thank you so much for your help.!!! bye!!

[Tdol]

I think it's a printing error- I'd use 'in case'.