The burning of crop or biomass residue releases various pollutants into the atmosphere, contributing to air pollution and climate change. Carbon Monoxide (CO): Incomplete combustion of organic matter produces carbon monoxide, a colorless and toxic gas that affects air quality and human health. Methane (CH₄): Biomass burning can also release methane, a potent greenhouse gas that contributes to global warming. Sulfur Dioxide (SO₂): If the biomass contains sulfur compounds, its combustion releases sulfur dioxide, which can cause respiratory problems and contribute to acid rain. Ozone (O₃) Formation: Ozone is not directly emitted from biomass burning. However, it forms secondarily in the atmosphere when pollutants such as nitrogen oxides (NOₓ) and volatile organic compounds (VOCs) react in the presence of sunlight. Therefore, option (D) 1, 2, 3 and 4 is correct.