Iron has various functions in the body. A well known function is its presence in the muscle as haemoglobin which helps transport blood. It is also present in the muscle (myoglobin); and in molecules (cytochromes)
Option a, b and c are examples of not practicing proper hygiene and they increase the chances of you getting diseases. Option D is the only example that practices proper hygiene.
D.hot air rising and cooler air falling. A is example of radiation or conduction. B is example of radiation. C is example of conduction. D is example of convection
