The correct answer is (d), tocopherol. Tocopherol is a type of vitamin E, which is an essential nutrient that the body cannot produce on its own. Vitamin E is found in many foods, including vegetable oils, nuts, seeds, and green leafy vegetables. It is important for the proper functioning of the immune system, the nervous system, and the reproductive system.
Glycogen is a type of carbohydrate that is stored in the liver and muscles. It is the body’s main source of energy. When the body needs energy, it breaks down glycogen into glucose, which is then used by the cells.
Amino acids are the building blocks of proteins. Proteins are essential for the growth and repair of tissues, the production of hormones and enzymes, and the transport of nutrients. The body can produce some amino acids, but others must be obtained from food.
Fat is a type of lipid that is stored in the body. It is a source of energy and helps to insulate the body. Fat is also important for the absorption of vitamins A, D, E, and K.
Therefore, the only compound that is not stored in the human body is tocopherol.