In C# why can't I pass another class' EventHandler reference and how can I get around it?

Question

If I have ClassA that has a public event, SomeEvent, and ClassC that has method, addListener, that accepts an EventHandler reference, why can\'t ClassB have a line that says

Answer 1

How can I get around it while staying reasonably close to my structure?

Use a.SomeEvent += handler instead.

Why does this restriction exist?

See Marc Gravell's answer.