C. for a number of reasons.
D. with changes in personality
71. From the passage we know that ____.
A. early treatment may stop Alzheimer's disease occurring
B. it is still unknown what causes the changes in the brain's nerve fibers
C. nerve fibers in the brain will cause Alzheimer's disease
D. when one suffers from Alzheimer's disease, he will be buried
E While in Banff, make time for a walk around town. A special treat is to go up the mountainside on the Banff Gondola for a surprising view of the valley below. Here is The Pines, whose cook has developed a special way of mixing foreign food such as caribou, wild boar, and reindeer with surprising sauces.
Best time to visit is during the off-season, from early May to mid-June, or in October. This way you can avoid sharing the high way with mobile(移动的) homes which can be pulled by cars. But whatever the season, take some lunch with you from Banff, because there are only a few food stops on the road.
Forty minutes north of Banff, side by side with the Banff National Park, sits world-famous Lake Louise. This surprisingly small body of water is attractive with towering mountains around it. Glaciers, huge masses of ice, moving very slowly against rocks, produce what is called glacier rock flour, making its water dark to see. It is worth taking a walk around the grounds of the Chateau Lake Louise, another beauty, proud of its early 20th century history.
Back on the road, and it's time to continue north past the astonishing Columbia Icefield, then turn off the highway and take the short road to the base of the Athabaska Glacier. You can rent ice cleats (夹板) and do some climbing or do a more pleasant snowmobile tour. Either way, you can enjoy endless beautiful sights.
Finally you'll reach Jasper, the usual turning around the place for the Banff-Jasper loop (回路). It's worth riding the Jasper Skytram, and be sure to visit the wonderful Jasper Park Lodge, also dating back to the 1920s. If you can have lunch there, do it. The restaurant has an adventurous menu and their wine list would put a smile on any visitor's face. 72. According to the passage, The Pines is a _____. A. place in which you can see many mobile homes B. mountain where you can get a good view of the valley C. town which happens to be near the Banff National Park D. restaurant where you can ask for some special kinds of food 73. What will probably happen when visitors come at the end of June? A. They may have trouble finding a restaurant. B. They may come across traffic jams. C. They may travel more easily with cars.