AAn airborne pathogen that lives in moist, warm environments.
BAn pathogen that is transmitted via mucous membrane contact.
CA pathogen that invades the body from the outside when its resistance is low.
DA pathogen that inhabits the human body at all times, and only causes illness when the body's defenses are weakened.
✓ Correct answer: D. A pathogen that inhabits the human body at all times, and only causes illness when the body's defenses are weakened.About one half of all human disease is caused by pathogenic prokaryotes that invade the body from the outside, avoid internal defense systems in the body, and reproduce effectively enough to cause harm. Opportunistic pathogens are normal inhabitants of the body, that at most times cause no ill effect and only cause illness when the body's defenses are weakened.
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Theory