Please Listen to the following TED talk and answer the questions followed. (09分20秒-10分07秒) According to the scientific research, the speaker concludes that_____.
A、CO2, methane, and ice sheets were feedbacks that amplified global temperature change causing these ancient climate oscillations to be huge
B、CO2, and methane were feedbacks that amplified global temperature change causing these ancient climate oscillations to be huge, even though the climate change was initiated by a very weak forcing
C、CO2, methane, and ice sheets were warning signals that amplified global temperature change causing these ancient climate oscillations to be huge
D、CO2, methane, and ice sheets were feedbacks that simplified global temperature change causing these ancient climate oscillations to be huge