Answer: A.
Explanation:
Palisade mesophyll cells contain the most amount of chloroplasts with an average of 30–70 chloroplasts per cell so they will be number 2 in the graph.
Spongy mesophyll cells contain less chloroplasts than their palisade counterparts to enable them have a larger surface area for gas diffusion.
The guard cells have the least amount of chloroplasts on average and so will be number 1. on the graph.
