How does the current extinction crisis differ from previous mass extinctions?

Step 1: Evaluate option (a). Previous mass extinctions occurred over thousands to millions of years, but the current crisis is ~1,000 times faster due to human impacts. Option (a) is incorrect. Step 2: Evaluate option (b). Past extinctions (e.g., Permian, Cretaceous) were triggered by natural events like volcanism or asteroids. The current Holocene/Anthropocene extinction is primarily caused by human activities (habitat loss, overhunting, pollution, climate change). Option (b) is correct. Step 3: Evaluate option (c). Mass extinction reduces biodiversity and disrupts ecosystems, harming planetary health long-term. Option (c) is incorrect. Step 4: Evaluate option (d). Recovery from past extinctions took 5–30 million years to rebuild biodiversity. Genetic engineering cannot rapidly restore complex ecosystems. Option (d) is incorrect. Final answer b