To answer this question, we need to understand the concepts of thread synchronization and the methods wait(), notify(), and notifyAll().
Option A) wait() - This option is correct. The wait() method is used to suspend the execution of a thread and releases the lock it holds. It allows other threads to acquire the lock and continue their execution. The thread will remain in a suspended state until another thread calls the notify() or notifyAll() method.
Option B) notify() - This option is incorrect. The notify() method is used to wake up a single thread that is waiting on the same object. It does not stop the execution of a thread, but rather notifies one waiting thread to resume execution.
Option C) notifyAll() - This option is incorrect. The notifyAll() method is used to wake up all threads that are waiting on the same object. It also does not stop the execution of a thread but rather notifies all waiting threads to resume execution.
Option D) exits synchronized code - This option is incorrect. Exiting synchronized code does not directly stop the execution of a thread. It simply releases the lock it holds and allows other threads to acquire the lock and continue their execution.
Therefore, the correct answer is option A) wait(). This option directly stops the execution of a thread by suspending it until another thread calls the notify() or notifyAll() method.
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