In the summer of 1999, a significant volcanic eruption occurred in the Pacific region, leading to a noticeable drop in temperatures across North America. This suggests that volcanic eruptions can lead to cooler atmospheric conditions.

Which of the following statements, if true, most seriously undermines this conclusion? (A) The temperature drop in North America was offset by an unprecedented heatwave in the southern states. (B) Historical data shows that volcanic eruptions have no correlation with temperature changes in the Arctic. (C) After the eruption, temperatures in the Midwest remained stable and did not show significant fluctuations. (D) The cooling effects of volcanic eruptions are often temporary and can be overshadowed by long-term climate change trends. (E) A volcanic eruption in the Caribbean led to increased rainfall in the region, but temperatures remained unchanged.