Officialy the shorthand name of Democratic Republic of the Congo is just Congo. You should just put that your using the common Wikipedia names not shorthand names.
Respectfully disagree. I intentionally referenced Wikipedia's shorthand listing (of sovereign states) i.e. the blue, clickable names. "Congo" alone would make it indistinguishable from Republic of Congo (once Congo-Brazzaville), which would have equal claim to "Congo".
It’s more commonly known as the United States, and not that extended part, and on the Countries Of The World Quiz, it’s also put as United States, but United States Of America is the more official name