Since the 1850s researchers have tried to show that variations in seasonal weather are connected in some ways with sunspots , the outward sign of an increase in the Sun's activity. However, sciences lacked evidence supporting such a link until the mid-1980s, when van Loon and Labitzke compiled statistical evidence suggesting that a link exists and that it involves winds in the upper atmosphere above the equator which reverse their direction from east to west or west to east, every twelve to fifteen months. This phenomenon is called the quasi-biennial oscillation (QBO), and although meteorologists have known about the QBO since the 1950s, until the 1980s no one recognized a subtle but statistically significant link between the QBO and certain pattern of weather. When the west to east direction of winds in the upper atmosphere coincides with periods of high solar activity that occur approximately every eleven years, winters in the eastern and central United States are very cold.
On this basis, some meteorologists predicted that the winter of 1988-1989 in the United States would be severe. However, the winter was a mild one overall, and the meteorologists' attempt to make the connection between the Sun and weather on the Earth appeared unsuccessful, until Barston and Liverzey proposed a hypothesis explaining why the prediction had failed. They argued that the prediction had not taken into account another important element in the climate: the more or less regular pattern of fluctuations in the temperature of the surface waters of the tropical Pacific Ocean.
Barston and Livezey noted that when the water temperature is abnormally high-the phenomenon called EL Nino—the changes of cold winter weather over North American increase. The opposite situation, when surface temperatures are well below normal—La Nina—is far less common. In fact, until late 1988 no one had seen the combination of La Nina, westerly winds in the upper atmosphere, and high solar activity.
Thus, according to Barston and Livezey, La Nina cancelled out the effect of the other two climatic factors and caused the mild winter of 1988-1989. Although this hypothesis is plausible, much research remains to be done before meteorologists can establish and explain the effects of increased solar activity on seasonal weather changes.
The author of the passage would most likely agree with which of the following statements about the link between increased solar activity and certain seasonal weather changes on the Earth?
题目类型：推断题
选项分析：定位最后一段Although this hypothesis is plausible,... increased solar activity on seasonal weather changes.虽然这里理论看起来可信，但是还需要further study去证实
选项A does not looking promising.错误
选项 B it is unlikely that such a link can be definitely established与文章内容不符，还有有意义的
选项C it is unlikely that future research will be able to confirm 可不可以被证实不知道，错误
选项D 正确
选项E Since the evidence clearly supports the existence of such a link, further research should focus on determining the implications与文章内容不符
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