244.Given: 1. public class TestSeven extends Thread{ 2. private static int x； 3. public synchronized void doThings(){ 4. int current = x； 5. current++；6. x = current； 7. } 8. public void run(){ 9. doThings()； 10. } 11. } Which statement is true?
(A) Compilation fails.
(B) An exception is thrown at runtime.
(C) Synchronizing the run() method would make the class thread-safe.
(D) The data in variable "x" are protected from concurrent access problems.
(E) Declaring the doThings() method as static would make the class thread-safe.