To solve this problem, we need to analyze the given statements:$\newline \bullet$Statement I: In C₃ plants, some O₂ binds to RuBisCO, hence CO₂ fixation is decreased.$\newline$ - C₃ plants use the enzyme RuBisCO for carbon fixation.$\newline$ - RuBisCO can bind to both CO₂ and O₂. When O₂ binds, it leads to a process called photorespiration, which decreases the efficiency of CO₂ fixation.$\newline$ - Therefore, Statement I is true.$\newline \bullet$Statement II: In C₄ plants, mesophyll cells show very little photosynthesis while bundle sheath cells do not show photorespiration.$\newline$ - In C₄ plants, photosynthesis is divided between mesophyll and bundle sheath cells.$\newline$ - Mesophyll cells fix CO₂ into a 4-carbon compound, which is then transported to bundle sheath cells where the Calvin cycle occurs.$\newline$ - Bundle sheath cells in C₄ plants are adapted to minimize photorespiration. However, mesophyll cells do play a significant role in the initial fixation of CO₂.$\newline$ - Therefore, Statement II is false because mesophyll cells are actively involved in photosynthesis.$\newline$Based on the analysis, the correct answer is:$\newline$Option 1: Statement I is true but Statement II is false.