Which of the following is a recognized national holiday in the United States?

Labor Day and Thanksgiving are both recognized national holidays in the United States. Labor Day is celebrated on the first Monday of September and honors the American labor movement and the contributions of laborers to the development of the country. Thanksgiving, observed on the fourth Thursday of November, is a time for families and friends to gather for a meal that often includes turkey and to give thanks for the harvest and blessings of the past year.

While Valentine's Day is celebrated on February 14, it is not classified as a national holiday; instead, it is considered a cultural or commercial observance and does not involve any federal recognition. The inclusion of both Labor Day and Thanksgiving as national holidays makes the answer encompassing both correct, highlighting the importance of these holidays in American culture and tradition.