I would say: This is most common.
3, 5, 6
Answer: Operating system
Explanation:
A computer's OS (operating system) is one of the type of computer software and the main function of an operating system is that it helps in managing the hardware, processes, memory and the software of the computer application.
An operating system basically providing the set of instruction to the computer for the communication purpose and perform various types of task in the computer system.
According to the given question, an operating system is refers to the software program that helps in coordinating all the task and the activities in the computer system.
Therefore, Operating system is the correct answer.
