By default, from which hardware component is the startup copy of the ScreenOS loaded?(Exhibit)

A.
ROM

B.
NVRAM

C.
TFTP server

D.
Internal Flash

E.
PCMCIA Card

Explanation:
Each Netscreen device has a similar design for its internal system components. Long-term storage on the device is stored into flash memory. Flash memory is a non-volatilentype of memory that retains information after the system is turned off. Some devices have a Personal Computer Momory Card International Association (PCMCIA) card slot for external storage. This card is still just flash memory, but it is removable; the internal flash is not. All of the component information that Netscreen needs to store is in flash memory, including ScreenOS log files, license keys, attack databases, and virus definitions.
Each Netscreen device also contains Random Access Memory (RAM). This is a volatile type of memory that is lost whenever the system is powered off or reset. When the Netscreen device powers on, and after the power on self test (POST) is completed, the ScreenOS image is loaded into RAM. After ScreenOS is up and functional, it loads the saved configuration file from flash memory. The configuration that is stored in RAM is called the running configuration. Whenever you make a change to the configuration it is always saved to the running configuration.