Answer:
A. a diagram showing the process by which photosynthesis takes place
Step-by-step explanation:
If the writer wanted to provide more information about the process of how leaves take in nutrients and energy, the graphic that would be best to add to the
passage would be a diagram showing the process by which photosynthesis takes place.
This is because, the diagram would best illustrate the process by which plants get and utilise vitality from the sun and how chlorophyll works.
Therefore, the correct answer is option A.