What is the blood component that carries water, waste, proteins, and nutrients?

Plasma is the correct answer because it is the liquid component of blood that serves multiple vital functions in the body. Comprised largely of water, plasma makes up about 55% of total blood volume and is responsible for transporting a variety of substances throughout the circulatory system. This includes not only water but also essential proteins, electrolytes, hormones, and waste products generated from cellular metabolism.

In contrast, red blood cells primarily function to carry oxygen from the lungs to the body tissues and return carbon dioxide to the lungs for exhalation. White blood cells play a crucial role in the immune system, helping the body to fight infections and foreign invaders. Platelets are essential for blood clotting, aiding in the prevention of excessive bleeding when injuries occur. Each of these components has distinct, specialized functions that support overall health, but it is plasma that is uniquely responsible for the transportation of water, waste, proteins, and nutrients.