Answer :
A reader-writer lock, when write-locked, only allows one thread to write to the locked resource, blocking all reading threads until it is released. Therefore option e. update and f. write
When a reader-writer lock is write locked, only one thread attempting to write can have it while all threads attempting to read must wait until it is unlocked. Reader-writer locks are a synchronization primitive used to control access to a shared resource in a concurrent computing environment. These locks allow multiple readers to access the resource concurrently, while writers require exclusive access. When a writer holds the lock, all other readers and writers are blocked until the writer releases the lock.
