Incremental upgrades of the kernel are distributed as:

A.
patches.

B.
fixes.

C.
hotfixes.

D.
service packs.

Explanation:
Incremental upgrades of the kernel are distributed as patches. For example, if you have version
1.1.45, and you notice that there’s a `patch46.gz’ out there for it, it means you can upgrade to
version 1.1.46 through application of the patch. You might want to make a backup of the source
tree first (`make clean’ and then `cd /usr/src; tar zcvf old-tree.tar.gz linux’ will make a compressed
tar archive for you.).