41.) This is true, as a citizen is labeled by time and must be protected by the country.
42.) A duty of American citizens is voting, as well as paying taxes. Those are basics, but the one that's also correct and is listed is serving on a jury, as you must be at least 18 years of age, or a citizen in the US.
43.) A person who was born in another country can become an American citizen through naturalization. They do this by being 18 years of age, being a permanent resident for 5 years, and filling out a form.