What describes processes and threads with a blocking system call of a single process control block $($PCB$)?$

Choose $2$ answers.

If one process is blocked, no other process can execute until the first process is unblocked.

If one thread is blocked, the next thread in the same task can be executed.

If one process is blocked, the next process in the same task can be executed.

If one thread is blocked, no other thread can execute until the first thread is unblocked.Which primitive is used to provide synchronization between processes?

Queue

Semaphore

Stack

Collection