Which two are valid configurations of an interface?()<br /> <img src="https://nimg.ppkao.com/2018-08/zhoulian/2018080816080647436.jpg?sign=676a676b1358c8ca7ffeccbd570f2e9f&t=62d14f12" />
A、A
B、B
C、C
D、D
A、A
B、B
C、C
D、D
A、A.Foo.beta() is a valid invocation of beta(). B、B.Foo.alpha() is a valid invocation of alpha(). C、C.Method beta() can directly call method alpha(). D、D.Method alpha() can directly call method beta().
A、A.p0 = p1; B、B.p1 = p2; C、C.p2 = p4; D、D.p2 = (ClassC)p1; E、E.p1 = (ClassB)p3; F、F.p2 = (ClassC)p4;