单选题：To register a source for an action event with a handler, use ___

To register a source for an action event with a handler, use __________. @[A](2)
A. source.setOnAction(handler)
B. source.addOnAction(handler)
C. source.setActionHandler(handler)
D. source.addAction(handler)





A.source.setOnAction(handler)
B.source.addOnAction(handler)
C.source.setActionHandler(handler)
D.source.addAction(handler)


答案：A