Excess of carbon dioxide in the body fluids is known as
Carbon dioxide is a gaseous product of the body's metabolism that is generally expelled out of the system. However, when the the level of Co2 in the body remain elevated or is found in excess, this tens to increase the levels of Co2 in the blood too. Such a condition, where there is excessive retention of carbon dioxide in the body is referred to as hypercapnia.
Therefore, the correct answer is option B.