The correct answer is A. Is that which benefits others while causing a disadvantage to the individual.
Explanation:
In biology, altruistic behavior occurs as one organism actions benefit other organisms either because these actions increase the reproductive fitness or the chances an organism survives and prevails over time. Additionally, altruistic behavior implies there is a disadvantage for the organisms acting in the benefit of others. For example, wolves or similar animals take food to those that did not participate in hunting, which means they help other wolves to survive on their own cost as this means less food for those that hunted. According to this, altruistic behavior "is that which benefits others while causing a disadvantage to the individual".
B is the incorrect statement, and therefore the correct answer.
A patient with sickle cell crisis will most likely complain of severe pain.
A patient with sickle cell disease have an abnormal amino acid composition of hemoglobin, leading to a comformational change to insoluble proteins whenever the red blood cell is deoxygenated; this leads to a change in shape from biconcave to sickle shaped. In sickle cell crisis, the abnormal RBC clump together (easily, because of their shape) then obstruct small blood vessels in the extremities and other organs, causing severe pain.
It is a covalent substance because there is a covalent bond between Hydrogen and Oxygen
