11. Although many brands of gasoline are sold on Haibei Island， gasoline companies there get all of the refined gasoline they sell from Haibei seaport's only storage tank， which is always refilled with the same quality of gasoline. Therefore， the brands of gasoline of sale on Haibei may be different in name and price， but they are identical in quality.
The conclusion drawn above depends on which of the following assumptions?
(A) Consumers are usually unaware of variations in the quality of the gasoline they buy unless those variations are announced by the gasoline companies.
(B) When tankers make gasoline deliveries at Haibei's seaport， the storage tank on Haibei always receives the same quantity of gasoline as that in the preceding delivery.
(C) There is a wide variation in the prices at which the different brands of gasoline on Haibei are sold.
(D) If any gasoline company on Haibei alters the quality of its gasoline before sale， the other gasoline companies also use methods before sale that result in the same change in the quality of their gasoline .
(E) The gasoline storage tank on Haibei is large enough to meet the needs of all of Haibei's different gasoline companies.
12.A group of paintings made approximately 15，000 years ago in a cave in the Loire River valley in what is now France depicts a number of different animals. One of the animals depicted seems to resemble the chiru， a rare antelope of the Himalayas.
Which of the following， if true， best supports the hypothesis that in painting the animal that resembles a chiru the cave artist painted a chiru with which she or he was familiar?
(A) There are numerous representations of imaginary animals in cave paintings of similar age.
(B) Fossilized remains of a chiru， approximately 16，000 years old， have been found at the northern end of the valley.
(C) The cave that contains the depiction of an animal that resembles a chiru contains stylized representations of plant life.
(D) Older caves from the same region contain no representations of animals that resemble a chiru.
(E) The antlers of the animal in the painting are longer than those of the mature Himalayan chiru.
参考答案：
DB