The correct answer is option 2, Vitamin C. Vitamin C is a water-soluble vitamin, which means it dissolves in water and can be easily excreted from the body if consumed in excess. Water-soluble vitamins are not stored in the body, unlike fat-soluble vitamins, which can be stored in fatty tissues and the liver.

Vitamin A (option 1) is a fat-soluble vitamin that is important for vision, immune function, and cell growth. Vitamin D (option 3) is also a fat-soluble vitamin that helps the body absorb calcium and promotes bone health. Vitamin K (option 4) is another fat-soluble vitamin that plays a crucial role in blood clotting and bone metabolism.

It`s important to know the solubility of vitamins to understand how they are absorbed, stored, and eliminated from the body.