Final Answer:
The inference from the text is that Climate change will have long-lasting effects on our environment (Option B).
Step-by-step explanation:
In Part A, the best-supported inference is that climate change will have long-lasting effects on the environment. This conclusion is drawn from various statements in the text that highlight the persistent impact of climate change on future generations, such as the mention of elevated greenhouse gas levels lasting three to five million years (Part B, Option B) and the acknowledgment that even if emissions stop today, climate change effects will continue (Part B, Option C).
Option B is the answer.