Enthuware

I slightly disagree with the option that run method is defined by Thread class, isn't it defined by Runnable interface?

No, it is declared by Runnable interface. It is defined by Thread class.
Also, just because a method is declared and/or defined by one class doesn't mean it cannot be declared and/or defined by another.

in the D-n-D screen, it is written "synchronize" instead of "synchronized", is it intentionally incorrect?

Regards, Paul

Yes, it is intentionally incorrect. You must use NONE for this.