What can be a result？（）

A.It is possible to synchronize static methods.
B.When a thread has yielded as a result of yield（）， it releases its locks.
C.When a thread is sleeping as a result of sleep（）， it releases its locks.
D.The Object.wait（） method can be invoked only from a synchronized context.
E.The Thread.sleep（） method can be invoked only from a synchronized context.
F.When the thread scheduler receives a notify（） request， and notifies a thread， that thread immediately releases its lock.

A.Compilation fails.
B.An exception is thrown at runtime.
C.The code executes normally and prints "foo"；
D.The code executes normally， but nothing is printed.

A.The output could be 5-1，6-1，6-2，5-2
B.The output could be 6-1，6-2，5-1，5-2
C.The output could be 6-1，5-2，6-2，5-1
D.The output could be 6-1，6-2，5-1，7-1