What term describes disease-causing agents like bacteria or viruses?

• A. Germs
• B. Pathogens
• C. Microbes
• D. Antigens

Answer: (B)

The idea here is to name disease-causing agents such as bacteria or viruses. Pathogens are organisms or particles that cause disease in a host. Bacteria and viruses are classic examples of pathogens. Other terms can be confusing: germs is a casual word that means disease-causing agents but isn’t precise; microbes refer to all microscopic life, not all of which causes disease; antigens are substances that the immune system recognizes, not the disease-causing organisms themselves. So, the term that fits best is pathogens. For example, the influenza virus is a pathogen, while many microbes in our gut are beneficial and not disease-causing, and antigens are things that the immune system detects.