The correct answer is option 1: Vitamin. Riboflavin is a type of vitamin, specifically known as vitamin B2. Vitamins are essential nutrients that our body needs in small amounts to function properly. Riboflavin plays a crucial role in various bodily processes, such as energy production, metabolism, and maintaining healthy skin and eyes. It is water-soluble, meaning it dissolves in water and cannot be stored in the body for long periods, so it needs to be replenished regularly through our diet. Riboflavin can be found in foods like milk, eggs, meat, leafy green vegetables, and whole grains. It is important to consume an adequate amount of riboflavin to support overall health and prevent deficiencies.