Answer : 4. "Booting"
Explanation :

1. Booting is a type of start-up sequence that starts the computer's operating system when the system is switched on.

2. This process involves some set of operations, which are performed when the computer is switched on. Knowing the boot sequence is important for optimizing and troubleshooting the computer.

3. It can be initiated by hardware such as a button press, or by software commands.

4. After it is started, there is no software in the main memory of the computer's central processing unit (CPU), so the software must be loaded into memory before it can be executed by some process.