Explanation:

Correct Option 2: Urea -60

The acid equivalent of urea is actually 80, not 60.
Acid equivalent is a measure of the potential acidity a fertilizer can contribute to the soil.
When urea is hydrolyzed in the soil, it releases ammonium ions, which can then be converted to nitric acid through the process of nitrification, leading to soil acidification.
Key point-
• Equivalent Acidity of Fertilizers:
-Anhydrous Ammonia: 148 meq/100 kg
-Ammonium Chloride: 128
-Ammonium Sulphate: 110
-Urea: 84
-DAP (Diammonium Phosphate): 77
-Ammonium Nitrate: 60
• Equivalent Basicity of Fertilizers:
-Sodium Nitrate: 29
-Calcium Nitrate: 21