Choose the most logical order of sentences from among the four given choices to construct a coherent paragraph.
A. These fluctuations are often caused by natural events such as volcanic eruptions or variations in solar radiation.
B. Understanding climate change requires analyzing long-term patterns in temperature, precipitation, and atmospheric composition.
C. However, human activities, particularly the burning of fossil fuels and deforestation, have accelerated changes in the Earth’s climate.
D. While the Earth’s climate has always undergone changes, recent shifts are occurring at an unprecedented rate.