About Question enthuware.ocpjp.v7.2.1499 :

[horst1a]

The question here is very tricky. Answer A shall be right. I preferred answer C.
But it says answer C is wrong, as in the answer there is no creaion of a Thread. Thats ok for me.
But in my eyes:
Answer A is wrong, as answer A also does not create a Thread and it is furthermore not necessary to overwrite the run Method.

[admin]

It is true that overriding run method is not necessary. The option does not claim such either.

The problem statement asks what can do you to define and start a thread. Whatever is given in Option A is certainly one way to do so. It doesn't claim that that is the only option.