For Part A, the correct answer is D. They have greatly reduced their landfill trash.
In Part B, the sentence that supports this conclusion is C. “Instead of sending these items to the landfill, people can set aside leftovers and use them for animal feed or compost them for fertilizer.” (paragraph 4). This indicates that residents are taking steps to reduce the amount of trash they send to landfills by reusing and composting materials.