Thank God! Someone finally made a quiz and called it the 'United States of America,' not just the 'United States.' People debated this with me on other quizzes. It's really not debatable. That IS our country's name. You don't hear people chanting 'U-S' at sporting events (it's always U-S-A!)! Another example, people say (in slang): 'the old U-S-of-A,' not 'the old U-of-S.' Sorry. This is a sore subject for me. I'm a veteran and take pride in my country and it's TRUE name.
Since you've asked (in capital letters) for FULL NAMES ONLY, then how come you've included the abbreviated form of United Kingdom of Great Britain and Northern Ireland? Also, United Mexican States is missing.