Listeners question

[Wilson Mui]

Can somebody explain to me the answer:
What is true of the listeners?

A. the return type is boolean
B. most components allow multiple listeners to be added.
C. a copy of the original event is passed into a listener method
I said B, and C, the mock exam said B only. I thought all listeners had methods which had a handle on an "event" object. Can somebody explain to me what my confusion is?

[Francis Siu]

hi Wilson
I think about twenty miniutes and find out a possible solution.
C. a copy of the original event is passed into a listener method
The answer does not say something before you need to do.
It may be tricky or I misunderstand it
Original event/event source should be registered first,than it can be passed into a listener method.
It may be a suitable answer

[John Lee]

yes, b only, event is not passed into listener.

[Robbie kyodo]

sometimes they asked you
What is the modifiers for event listener ?
should be public for ALL