The correct option is B hormones
Most of the body functions are regulated by hormones like growth, vegetative and sexual development, thermal regulation, cellular oxidation, metabolism of carbohydrates, proteins, fats, etc. Hormones are needed in very small quantity to carry out these functions. Some hormones are proteinaceous eg: insulin (regulates sugar metabolism), growth hormone of pituitary, parathyroid hormone parathormone (regulates calcium and phosphate transport).