के.व्ही.आय.सी. जैव वायू प्रकल्पाचे फायदे असे आहेत :
(a) स्वच्छ आणि उच्च उष्मांक इंधन पुरवठा.
(b) अनएरोबीकरित्या पचलेली स्लरी देते.
(c) जंगलाचा नाश कमी करते.
(d) नाईट सॉईलचा रोगजनक भार कमी करते.
वरीलपैकी कोणते/ती विधान/ने योग्य आहे/आहेत ?
(1) (a), (b) आणि (d)
(2) (b), (c) आणि (d)
(3) (a), (b), (c) आणि (d)
(4) (a), (b) आणि (c)

The correct answer is Option C ((a), (b), (c) and (d)).

Key Points:
• KVIC Floating Drum Biogas Plant: Developed by the Khadi and Village Industries Commission (KVIC) in 1962, featuring a floating mild-steel gas holder over a digester pit.
• Comprehensive Benefits:
• Clean Fuel: Supplies smokeless, high-calorific fuel gas (~20 MJ/m³) replacing firewood and dung cakes (Statement a).
• Nutrient-Rich Slurry: The digested effluent slurry is weed-free, odorless, and enriched with nitrogen and phosphorus (NPK) for agricultural application (Statement b).
• Forest Conservation: Eliminates the reliance on firewood, directly curbing deforestation in rural belts (Statement c).
• Sanitation Enhancement: When integrated with community toilets/night soil, anaerobic digestion kills helminth eggs and pathogenic microorganisms (Statement d).
• Official Key: All four statements are correct, confirming Option (3).
• Key Takeaway: The KVIC biogas model delivers high-calorific clean fuel, enriched digested slurry, prevents deforestation, and treats human waste safely.