वन संसाधन प्रबंधन एवं नीतियां

Acid rain is caused by emissions of sulfur dioxide ($\text{SO}_2$) and nitrogen oxides ($\text{NO}_x$), which react with water molecules in the atmosphere to produce sulfuric and nitric acids. Option analysis: (A) Methane and ozone are greenhouse gases and secondary pollutants, not the primary causes of acid precipitation. (B) Sulphur dioxide and nitrous oxides are the primary acid-forming gases. (C) Methane does not cause acid rain. (D) Carbon dioxide causes normal mild rainwater acidity ($\text{pH} \approx 5.6$), but severe acid rain is due to $\text{SO}_2$ and $\text{NO}_x$.

Statement (I) is correct because individual farmers adopt farm forestry on commercial principles to maximize economic returns on their land and capital. Statement (II) is correct because traditional smallholder farm forestry typically utilizes peripheral farm boundaries, bunds, and homestead margins with low tree densities requiring negligible extra expenditure. Option analysis: (A) Both Statement (I) and Statement (II) are correct. (B) Statement is not incorrect. (C) Statement (II) is also valid. (D) Statement (I) is also valid.