A new kernel version needs to be compiled to use a new feature. If the old kernel configuration file is available, which make target will only update the configuration file for the new kernel version? (Please enter only the make target).

Answer: oldconfig

Explanation:
oldconfig will read the defaults from an existing .config and rewrite necessary links and files. Necessary means what new features are added then the running kernel. Use this option if you’ve made minor changes to source files or need to script the rebuild process.
Note that oldconfig will only work within the same major version of the kernel. You cannot, for example, use a 2.4.x .config with the 2.6.x kernel.