NURSING ANM AND GNM

Detailed explanation-1: -It is the iron atom that binds oxygen as the blood travels between the lungs and the tissues. There are four iron atoms in each molecule of hemoglobin, which accordingly can bind four molecules of oxygen.

Detailed explanation-2: -These heme groups contain positively charged iron (Fe2+) molecules, which can reversibly bind to oxygen molecules and transport them to various areas of the body. Hence, option B is correct.