Process is: (a) contents of main memory (b) a job secondary memory (c) a program in execution (d) program in High level language kept on disk

Why Process is a Program in Execution?

• A process may consist of many threads of execution that carry out instructions simultaneously, depending on the operating system.
• When a programme is launched under UNIX and some other operating systems, a process is launched (either by a user entering a shell command or by another program). 
• A process, like a task, is a running programme that has a specific set of data associated with it so that it may be monitored. A shared application typically has one process running for each user at some point throughout its runtime.
• A process can start a child process, often known as a subprocess (and the initiating process is sometimes referred to as its parent ). A child process shares some resources with its parent process and is a copy of the latter, but it cannot continue to function if the latter is terminated.
• Through many forms of interprocess communication, processes can exchange data or coordinate their operation ( IPC ).

Summary:

Process is: (a) contents of main memory (b) a job secondary memory (c) a program in execution (d) program in High-level language kept on disk

A program in execution is a process. The computer software that is run by one or more threads is called a process. An instance of software running on a computer is called a process. The term “task,” which is used in various operating systems, is similar in meaning to this.