This option is correct as in multiprogramming systems, one or more programs are active at the same time. Here, one process can use the CPU and other the input output devices, while some programs may be in a waiting state.

This layer in OSI interfaces directly to the users and performs common application services for the application processes.

This operating system is a group of computers that provides services to other computers connected through a network.

This option is correct because in real-time operating systems, a rigid time limit is placed on the operation of the processor or on the flow of data.

This option is correct because in this, time is divided equally for each process. Each process runs for one time quantum if it does not complete in that time quantum, it is preempted and the CPU is given to another process scheduled to run.

This option is correct because in Round-robin scheduling, a fixed time quantum is assigned to each process and if the process does not complete in that time quantum it is preempted and the next process in the ready queue may start its execution.

This property in distributed systems allows sharing of information by a number of different computers that are connected to each other in a network.

 In a time-sharing operating system, when the time slot given to a process is completed, the process go to the READY state.

The distributed systems are physically separated computers, which are combined together through a network so that they can communicate and share computational tasks and provide a rich set of features to the users.

This is a non-premptive scheduling algorithm. FIFO strategy assigns priority to processes in the order in which they request the processor. No other process can preempt the process until it voluntarily leaves the control of the CPU. Hence, it cannot be preemptive. So, this option is correct.

This option is correct because for time sharing systems each user needs to get a share of the CPU at regular intervals.