46 What is the best title for this passage?
(A)Tree Rings in the Colorado River Valley
(B)Tree Rings and Climate History
(C)Trees and People in Complacent Life
(D)The Protection of Trees in Colorado

When provided with continuous nourishment, trees, like people, grow “complacent自滿、自鳴得意”—the word tree ring年輪 scientists use to describe trees like those on the floor表面, （房間的）地板 of the Colorado River Valley, whose roots tap into thick reservoir水庫；蓄水池 of moist soil.

Complacent自滿、自鳴得意 trees aren’t much use for learning about climate history, because they pack on wide new rings of wood even in dry years. To find trees that feel the same climatic pulses as the river, trees whose rings widen and narrow from year to year with the river itself, scientists have to climb up the steep, rocky  slopes斜坡 above the valley and look for gnarled（尤指因為年老或壞天氣的侵害而）粗糙, ugly trees, the kind that loggers樵夫 ignore.

For some reason such “sensitive” trees seem to live longer than the complacent ones.

“Maybe you can get too much of a good thing,” says Dave Meko, a tree-ring scientist who has been studying the climate history of the western United States for decades.

Tree-ring fieldwork實地考察 is hardly expensive, but during the relatively相對地 wet 1980s and early ’90s, Meko found it difficult to raise even the modest funds for his work.

“You don’t generate interest to study drought干旱 unless you’re in a drought干旱,” he says.

電腦直譯:

當提供連續的營養，樹木，像人一樣，長"自滿"—— word 樹木年輪科學家用來描述類似美國科羅拉多河流域，其根打入厚油層的潮濕的土壤在地板上的樹木。因為他們對寬新環包裝乾旱年甚至自滿樹不是木材的用太多的關於氣候歷史、學習。要找到感覺到河邊的同一氣候脈衝的樹，樹其圈擴大和縮小與本身，這條河每年科學家必須爬上陡峭、岩石斜坡上方谷的記錄器忽略的那種杖、醜陋的樹木，看看。由於某種原因這種"敏感"樹似乎比自滿的長壽。戴夫·馬茲，幾十年來一直研究的美國西部氣候歷史的年輪科學家說："也許你可以得到太多的一件好事"。樹木年輪田野調查幾乎不貴，但較濕八十年代和九十年代初，在馬茲發現