Answer:
I believe it's D, reaction time.
Answer:
transport, protection and regulation
Explanation:
Blood transports the following substances: Gases, namely oxygen (O2) and carbon dioxide (CO2), between the lungs and rest of the body. Nutrients from the digestive tract and storage sites to the rest of the body. Blood absorbs and distributes heat throughout the body. It helps to maintain homeostasis through the release or conservation of warmth. Blood vessels expand and contract when they react to outside organisms, such as bacteria, and to internal hormone and chemical changes.
