Answer: Glomus.
- A Rhizobium
- B Glomus
- C Azotobacter
- D Anabaena
Correct answer: B. Glomus
Explanation: Glomus is a mycorrhizal fungus that helps plants absorb phosphorus from the soil, functioning as a biofertilizer.
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