C. Loss of calcium.
Kwashiorkor is a protein malnutrition.
Marasmus is a protein deficiency.
Loss of Vitamin C is just Vitamin C deficiency, also known as scurvy or scorbutus.
Ask this in the physics area next time please, but turn to someone you trust or if your young an adult, like your parents or your teachers. Maybe even your friends. No matter what age tell someone and if they don't know then get medical help if they can't.
Human behavior which can be seen by other people and observed by other people is usually also the behavior which is often subject to measurement, control, and experimentation in psychological experiments. The field which does this is psychology.
