On which two components of a router can a copy of a running-configuration file be saved manually by an engineer for backup purposes? (Choose two.)

NVRAM (Non-Volatile RAM) is the standard destination for saving a running configuration using the 'copy running-config startup-config' command; it persists across power cycles and is the normal backup location.

Flash memory stores the IOS image but can also hold configuration files using a command such as 'copy running-config flash:filename.cfg', making it a valid secondary backup location that also survives reboots.

ROM contains the bootstrap program and POST routines and is read-only; it cannot be written to by an engineer.

RAM holds the running configuration while the router is operational, but it is volatile - its contents are lost when the device is powered off or reloaded.

DRAM is the physical memory technology used to implement RAM on a router; it is equally volatile and cannot be used as a persistent backup location.