Studies have shown that photosynthesis, the process by which plants manufacture life-sustaining proteins from sunlight and carbon, is actually intensified if the level of carbon dioxide in the atmosphere is increased.
Your task
Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.
Common trap
Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.
Winning move
Predict what a right answer must do, then test each choice against the conclusion-evidence gap.