该图是低、中、高三个不同纬度的自然带(生态系统)物质流动示意图，(图中圆圈的大小)表示所储存养分百分比的多少，箭头的粗细表示物质养分的大小。读图回答26～27题。

小题1:对土壤、生物量、枯枝落叶在生态系统所储存养分的比重大小，最主要的影响因素是(　　)

A．气候条件

B．土壤条件

C．生物条件

D．地质条件小题2:图中所示三个自然带纬度由低向高排列的顺序是(　　)

A．①②③

B．②①③

C．③①②

D．③②①

In June 1985, two British mountaineers Joe Simpson and Simon Yates made the first-ever climb of the 21,000-foot snow-covered Siula Grande mountain in Peru. It was an exceptionally (26) job, but nothing compared to what was to (27) . Early in the process, Simpson (28) and broke his right knee. Yates could have (29) him but managed to find a way of (30) him down the mountains on a rope in a series of difficult drops. Then Simpson fell into a crevasse and Yates eventually had no (31) but to cut the (32) , completely convinced that his friend was now (33)

In his book on the (34) , Joe Simpson wrote:

(35) I looked at the distant moraines, I know that I must at least try I would probably (36) there among those rocks. If I died, well, that wasn’t so (37) , but I wouldn’t have (38) waited for it to happen. The (39) of dying no longer affected me as it had in the crevasse at first. I now had a chance to (40) it and struggle against it.

The survival of Yates himself was (41) . That Simpson somehow found a way of (42) out of the crevasse after 12 hours and then crawled and (43) himself six miles back to camp, (44) three days and might without food or drink, would be considered as a heroic fiction. But in fact it was so (45) .

39（）

A.horror 

B.dream 

C.picture 

D.imagination