C4 plants respond to higher temperatures and show higher rates of photosynthesis, while C3 plants have a much lower temperature optimum . The statement in Option B is incorrect because it claims C4 plants have a lower temperature optimum. The other statements are correct: CO2 concentration up to 0.05% enhances fixation ; Tomatoes are C3 plants used in greenhouses for higher yields ; Light saturation occurs at 10% of full sunlight .