Howdy,
We should have been much more explicit and stated that these two classes were NOT in the same file. I *can* tell you that this is not an issue in the real exam.
For one thing, as the previous post said, the line numbers are given to suggest that these may be different files. If the numbering starts at 1 and continues without missing a line, then you're looking at a single source file. If the numbering does NOT start at 1, then you're looking at a code snippet and not a complete file.
BUT... you will NEVER be tested on something that requires you to get your information from the line numbering. In other words, the line numbering is just there to help make things more obvious, but NEVER to be used as part of your question.
If you WERE going to be tested on whether you knew that two public classes could not be in the same file, it would either EXPLICITLY say, "Given two classes in the same file..." OR it would just be a statement like,
What is true about source code files?
A) You can have more than one public class in a source code file.
[which you would NOT select as the right answer...]
I hope that helps, and we're sorry for the confusion!
This stuff is confusing enough already...
cheers,
Kathy