Which of the following is NOT one of the busiest candy selling holidays?

New Year's Day is indeed not one of the busiest candy selling holidays. The primary candy selling holidays are typically those that involve gifting or celebration, where sweets play a significant role. Halloween, Valentine's Day, and Christmas are all occasions when candy sales surge significantly; Halloween is famous for trick-or-treating and candy consumption, Valentine's Day sees a rise in chocolate sales as gifts, and Christmas often includes a variety of festive treats and candies as part of holiday celebrations. In contrast, New Year's Day does not traditionally feature the same emphasis on candy, making it less significant in terms of candy sales compared to the other holidays listed.