About Question com.enthuware.ets.scjp.v6.2.416 :

[stoci]

How is A correct? I thought Runnable was an interface and could therefore not be instantiated? What are you passing to 'Thread t' if 'Runnable a' isn't instantiated?

[admin]

You are right. An interface cannot be instantiated. But here in option A, when you do new Runnable(){ ... } you instantiate an anonymous class that implements Runnable interface.

HTH,
Paul.

[stoci]

Thanks, that makes sense.

[lavinia]

Why the correct answers are not OnlyA and OnlyC because you cannot put them together the A and C portions of code, because they use same identifier a as a Thread or as a Runnable, so you can put only one piece of code once, A or C. Otherwise what sense makes the last two options?

[admin]

That is because the question wants you to select two options. So if one thinks that option C is not right and A is right, he can select A and Only A.
select the options Only A and Only C, will not make sense.

Finally, the right anwer is A and C.

HTH,
Paul.