Final answer:
The wait(), notify(), and notifyAll() methods are defined in the Object class because they are used for inter-thread communication and synchronization, allowing threads to wait for conditions and be notified when they change.
Step-by-step explanation:
The wait(), notify(), and notifyAll() methods are defined in the Object class rather than the Thread class because they are used for inter-thread communication and synchronization.
These methods allow threads to wait for a condition to be met, and then be notified when that condition changes.
By defining these methods in the Object class, any object can be used as a monitor to control access to a shared resource, regardless of whether it is a Thread object or not.