Final answer:
Carbohydrates are used primarily for energy and unlike proteins, vitamins, and water, do not play a significant role in the regulation of body processes.
Step-by-step explanation:
The only class of nutrients that does not function in the regulation of body processes is carbohydrates(B). While carbohydrates are primarily used for energy, proteins, vitamins, and even water play a role in regulation. Proteins act as enzymes, hormones, and contribute to the immune response. Vitamins and water are crucial for various regulatory functions including metabolism and maintaining homeostasis.
Carbohydrates are macro-nutrients along with proteins and lipids, but unlike the other macro-nutrients, they are not known for regulatory functions. Essential nutrients like vitamins, minerals, some amino acids, and fatty acids are crucial for proper body functions and must be obtained through food because the body cannot synthesize them in adequate amounts. In contrast, non-essential nutrients can be synthesized by the body.