Name two national U.S. holidays.

The correct answer includes Martin Luther King Jr. Day and Labor Day, both of which are recognized as national holidays in the United States. Martin Luther King Jr. Day is celebrated on the third Monday of January each year, commemorating the civil rights leader's contributions to the American civil rights movement. Labor Day is observed on the first Monday of September, honoring the American labor movement and the achievements of workers.

In contrast, choices that include holidays such as Easter do not qualify as national holidays since Easter's observance varies and it is not recognized as a public holiday in the same way as the others listed. Other holidays, while significant, may not fit the criteria of being declared as national holidays, which is something to consider when identifying the correct answer.