question: What sentence would provide a factual answer to this question: "Which is the best thing to do for a neighborhood?"

answer: planting native plants has a positive impact on an ecosystem

question: What sentence would provide a factual answer to this question: "What can cause light to bounce off an object?"

answer: when light hits a reflective object , that light bounces off that object

question: What sentence would provide a factual answer to this question: "The best time to have an all-day BBQ in the northern hemisphere is"

answer:
the amount of daylight is greatest on the summer solstice