Final answer:
The function that is not related to BIOS is 'Provides low level drivers for system devices.' BIOS is responsible for system setup entry and testing essential devices, but it doesn't provide low-level drivers for them.
Step-by-step explanation:
The identify which of the listed options is not a function of the Basic Input/ Output System (BIOS). Let's review the functions listed: Provides entry into system setup (CMOS). Tests essential devices before the system mounts operating system. Provides low level drivers for system devices
The BIOS is responsible for providing entry into the system setup, often referred to as CMOS where users can modify system settings. It also performs a Power-On Self Test (POST) to test essential devices and ensure they are working properly before handing over control to the operating system. However, providing low-level drivers for system devices is not a primary function of BIOS. Instead, the operating system typically manages drivers that facilitate communication between the system and hardware devices. Therefore, the correct answer is: c) Provides low level drivers for system devices. This option is not a function of BIOS.