Question

a white blood cell engulfing a bacterium is an example of blood functioning in
multiple choice
communication
protection
maintenance
transportation

Explanation:

White blood cells (leukocytes) are part of the immune system. One of their key functions is to protect the body from pathogens like bacteria. When a white blood cell engulfs a bacterium (a process called phagocytosis), it is removing a potentially harmful organism, which is a protective function of the blood. Communication in the context of blood could relate to transporting signaling molecules (like hormones), but that's not the case here. Maintenance might refer to maintaining pH or temperature (blood does help in thermoregulation etc., but phagocytosis is more about protection). Transportation is about moving substances (like oxygen, nutrients, waste) in the blood, which is not what's happening when a white blood cell engulfs a bacterium.

Answer:

B. protection