Correct answer: C) France
North America is a continent geographically. It is not all under a single government.
Los Angeles has significant population and some territorial size, but its city government is not sovereign. It is under a state government (California) and a national government (the United States).
Similarly, Texas -- at this point in history -- is not independently sovereign, but is one of the 50 states that make up the USA as a true state with all the characteristics listed. There was a time in Texas' history when it was a sovereign state on its own -- during the years of the Republic of Texas, which existed from 1836 to 1846.