Answer: (c) Introducing drought-resistant plant varieties that can photosynthesize efficiently even in dry conditions could potentially benefit photosynthesis.

• • Explanation: Options (a), (b), and (d) all contribute to a decrease in photosynthesis. Deforestation reduces the number of plants photosynthesizing, air pollution blocks sunlight, and fossil fuel use increases greenhouse gases that can affect plant health.

Answer: (c) Chlorophyll absorbs sunlight energy for use in photosynthesis, initiating the process.

• • Explanation: Chlorophyll acts as a light-absorbing antenna, capturing the energy needed to drive the chemical reactions of photosynthesis. Options (a), (b), and (d) describe different functions within the plant.

Answer: (c) The Calvin cycle uses energy from ATP( Adenosine Triphosphate) and NADPH (Nicotinamide Adenine Dinucleotide Phosphate) generated earlier to fix carbon dioxide into organic molecules, primarily glucose.

Explanation: The Calvin cycle doesn't directly involve capturing light energy or splitting water. Option (d) describes cellular respiration, not photosynthesis.

Answer: (d) Photosynthesis occurs primarily in the leaves of plants, where chloroplasts containing chlorophyll are present.

• • Explanation: While roots play a role in water uptake, photosynthesis takes place in the leaves. Options (a), (b), and (c) accurately describe the process of photosynthesis.

Answer: (c) Implementing stricter regulations to control air and water pollution would directly address factors that hinder photosynthesis, such as reduced sunlight availability and plant stress.

• • Explanation: While all the options contribute to a more sustainable environment, option (c) most directly targets the factors affecting photosynthesis. Option (a) focuses on a specific source of pollution, option (b) addresses soil health but not directly photosynthesis, and option (d) focuses on alternative energy but doesn't directly improve photosynthesis.