What command merges the startup-config file into the running-config in RAM?

The command that merges the startup-config file into the running-config in RAM is "copy startup running." This command effectively copies the contents of the startup configuration file, which is stored in NVRAM, into the running configuration, which exists in RAM.

When you execute this command, it integrates the predefined settings and configurations from the startup-config into the current configuration that the router or switch is actively using. This is particularly useful when you want to ensure that all necessary configurations are in place without completely overriding the existing running configuration, which may have changes that you want to retain.

Other options, while they may suggest similar concepts, do not accurately represent the correct command or action. For instance, "copy start run" uses incorrect shorthand, "merge startup run" does not correspond to any valid Cisco command syntax, and "load startup config" implies an action that does not match the direct copying of configurations into the running state. Thus, "copy startup running" is the correct command used for merging startup configurations into the running configuration effectively.