Many people like the vi text editor but the default bash command line editor recognizes emacs keystrokes.
What command entered into a bash initialization file will have bash recognize vi keystrokes after login?

A.
history -p vi

B.
alias emacs=vi

C.
HISTCMD=vi

D.
set -o vi

E.
unset emacs

Explanation:
You can switch the internal bash commandline editor by using the set -o command either directly in the command line or in the .bashrc file (or any other start script).