These positions were in (24) Switzerland Prague and Germany.

Correct this portion of the sentence

Switzerland Prague

Switzerland, Prague,
Switzerland Prague,
Switzerland, Prague
no error
I think it is C...?

It's probably right. However, some grammarians would also use a comma after Prague.

I'm bothered by the lack of parallelism. Switzerland and Germany are countries. Prague is a city.

Thank you both....:)

The correct way to write this portion of the sentence is:

Switzerland, Prague,

You are correct, option C.

In this case, Switzerland and Prague are different places, so they should be separated by a comma to indicate that two different locations are being mentioned. By inserting a comma between "Switzerland" and "Prague," the sentence becomes grammatically correct.