[单项选择]

Which country is the second largest oil exporter

Canada is the second largest country in the world in area, although its (21) is only some 25 million, most (22) in a 200-mile strip (23) the southern border. Over 25 percent of the (24) number live in the three main cities. The northern areas of the country are almost uninhabited (25) for isolated settlements.
Canada is (26) a rich country, and its national (27) per capita is the fifth highest in the world, but its economy in recent years has been rather (28) , because of the varied nature of what it does.
Over the last three years, the Canadian economy has been hard (29) by failing oil prices and by rising US interest (30) . This has (31) to a steep fall in industrial production-by as much as a fifth since 1981. Some (32) now think Canada is on the (33) to recovery, though more cautions spirits say that no (34) can be expected until there is
A. caused 
B. moved 
C. amounted 
D. led