Answer: They are species-specific and do not harm non-target organisms.
- A They are broad-spectrum agents capable of killing nearly all insect pests
- B They are species-specific and do not harm non-target organisms
- C They remain heat-stable and persist for years within soil reservoirs
- D They produce potent chemical toxins that diffuse through plant tissue
Correct answer: B. They are species-specific and do not harm non-target organisms
Explanation: Baculoviruses (genus Nucleopolyhedrovirus) are species-specific and narrow-spectrum, affecting only the target insect pest without harming other organisms or the environment.
Sewage passes through physical removal (primary), then aerobic biological treatment where microbes form flocs that consume organic matter (secondary); the settled activated sludge is then digested anaerobically to produce biogas - a deliberate switch from aerobic to anaerobic conditions between stages.
Concept context
Microorganisms in food, medicine, sewage treatment, biocontrol, and biofertilizers