A passage is given below followed by several conclusions which can be drawn from the facts stated in the passages. You have to examine each inference separately in the context of the passage, decide upon its truth or falsity, and choose the conclusion that best supports the passage. 

There are many types of problem molecules in the body, and each type is specific to its functions. For example, proteins such as keratin and collagen give strength and elasticity to hair, as well as to skin and tendons. Proteins are classified according to their functions. Not only proteins are problematic in nature, few are very vital for maintaining the balance in the human body. Haemoglobin and myoglobin are the oxygen-binding proteins of the blood and the muscle, respectively. Ovalbumin, the principle protein egg white is responsible for the setting and foaming properties of eggs. A particularly important group of proteins known as enzymes, directs all the body cells to produce chemical reactions. These reactions provide the basis of every type of cell activity, including growth, repair, the production of energy and the excretion of waste products.It is important to understand that the different elements lead to the proper functioning of the body taking the several conditions into consideration.  

The passage, if true, is best supported by which of the following conclusions?