Answer:
A. proteins
Step-by-step explanation:
A is essential for the proper functioning of our body. It also helps you lose weight, gain lean mass and even ward off the desire for calorie foods. On the other hand, its lack can cause numerous problems such as fatigue, thinning hair, low immunity, poor quality of skin, nails and hair, among other problems.
Our muscles, cartilage, ligaments, skin, hair and nails are basically made up of protein, which in turn is made up of amino acid chains. If our body is low in protein we will have problems in these places and many others. An example of protein deficiency can be seen in the question above, where Sam has poor quality skin and hair.