The correct answer is: A. size (heads, cylinders, sectors)
CMOS, or Complementary Metal Oxide Semiconductor, is a small amount of static RAM that stores basic configuration information for your computer. This information includes the date and time, the type of processor installed, the amount of memory, and the hard drive configuration.
The hard drive configuration includes the size of the hard drive, the number of heads, cylinders, and sectors, and the type of interface used. This information is used by the BIOS to initialize the hard drive during the boot process.
The other options are incorrect because they are not stored in CMOS. IRQ stands for Interrupt Request. It is a number that is used to identify a device that is requesting attention from the CPU. Free space is the amount of unused space on a hard drive. Virus alert is a feature that some antivirus programs use to notify the user if a virus is detected on the computer.