I believe it is “animals and plants caanot directly use all the nitrogen found in our atmosphere”
Vitamin B plays an important role in the human body. Vitamin B forms an important portion of the co-enzymes which is an important enzyme. Co-enzymes Vitamin B12 also plays role in various metabolic processes such as fat metabolism, carbohydrate metabolism and protein metabolism.
Objective, since objectivity means the evidence is not biased in any way.