Q1. [1] medium thorough-understanding
Which of the following correctly explains why biogas is considered a more efficient use of cattle dung than burning it as dung cake?
(A) Dung cake produces more heat per kilogram than biogas.
(B) Biogas yields energy AND improves manure quality, while burning dung cake destroys its value as manure.
(C) Biogas plants are cheaper to build than burning dung cake directly.
(D) Burning dung cake releases harmful nuclear radiation.
- A Dung cake produces more heat per kilogram than biogas.
- B Biogas yields energy AND improves manure quality, while burning dung cake destroys its value as manure.
- C Biogas plants are cheaper to build than burning dung cake directly.
- D Burning dung cake releases harmful nuclear radiation.
Generated by claude-sonnet-4-6 · 2026-06-26 13:35 · grounding rag
Model Answer
(B) Biogas yields energy AND improves manure quality, while burning dung cake destroys its value as manure.
Explanation
The textbook states: "Biogas is by far the most efficient use of cattle dung. It improves the quality of manure and also prevents the loss of trees and manure due to burning of fuel wood and cow dung cakes." It also notes that using dung cake is discouraged because it "consumes most valuable manure which could be used in agriculture." Option B captures both advantages — dual benefit of energy + manure — making it the correct answer. Options A, C, and D are factually incorrect or unsupported by the text.