Problem related to greenhouse warming

Question

Problem: Which of the following statements concerning atmospheric CO₂ levels or greenhouse warming is FALSE?

Group of answer choices

• During the last part of the Mesozoic Era (the Cretaceous), atmospheric CO₂ levels were much higher than they are at present.
• Greenhouse warming only occurs as a result of human activities, such as fossil fuel burning, industry, and deforestation.
• Greenhouse gases are ones that do not absorb most incoming solar radiation but do absorb outgoing terrestrial radiation.
• At present, atmospheric CO₂ levels are higher than they have been at any time over the past three million years of Ice Ages.
• Natural ecosystems can handle slow changes more easily than fast ones, so the rate at which CO₂ rises is a crucial factor.