Hi Maria,
I would say:
d) wait it's an Object method and releases the lock on the particular object whose reference was used to call it.
e) stop it's a
Thread method and releases all the locks one Thread has.
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a) yield keeps the locks and only allows Threads that are in a runnable state (not waiting on a lock for instance) to run.
b) sleep keeps the lock and temporarily cease execution for the specified time
c) interrupt is called from another Thread on a Thread that is waiting, sleeping, or blocked in a I/O
d) suspend holds its threads.