Answer: B. Metabolism Responding to the environment
Explanation: Plants and other photosynthetic organisms have an amazing ability to move towards the sunlight when needed in order to keep up with their photosynthesizing. They will always do this when they're hungry and if you've seen an overgrown plant you know they always want to keep eating, so they will do whatever it takes to make more food, and photosynthesize even more. So, they respond to their environment and follow the sun.
