Which command would you use to apply a diff file to an original?

A.
cat diff-file >> kernel

B.
patch > diff-file

C.
cat diff-file << kernel

D.
patch < diff-file

E.
patch << diff-file

Explanation:
patch takes a patch file patchfile containing a difference listing produced by the diff program and applies those differences to one or more original files, producing patched versions. Normally the patched versions are put in place of the originals. Running patch command by taking input from the diff-file