GWD-TN-18 Q10 (GWD 27-Q10)

kikichen1111

搜了一下发现好像都没有人问过。。答案是D，实在不明白B哪儿错。。而且B和D其实就是讲的一个意思啊，都在原文讲到。。

原文：A few skeptics have argued that the concentration of mass necessary to explain the speed of the whirling gas is not necessarily a black hole: the concentration in M87 might be a cluster of a billion or so dim stars.

Q10: The skeptics mentioned in the first paragraph would be most likely to agree with the astronomers mentioned in line 13 about which of the following statements concerning the galaxy M87?

A.The speed of the gas whirling around the center of M87 is caused by a dense object that is not a black hole.

B.The concentration of mass at the center of M87 is probably a large cluster of dim stars.

C.The presence of a black hole at the center of M87 is the most likely explanation for the speed of the gas whirling about the galaxy’s core.
D.The speed of the gas whirling around the center of M87 is caused by a large concentration of mass at the core of M87.
E.The gravitational influence of a star cluster would not be strong enough to account for the speed of the gas whirling around the core of M87.

B.The concentration of mass at the center of M87 is probably a large cluster of dim stars.

C.The presence of a black hole at the center of M87 is the most likely explanation for the speed of the gas whirling about the galaxy’s core.
D.The speed of the gas whirling around the center of M87 is caused by a large concentration of mass at the core of M87.
E.The gravitational influence of a star cluster would not be strong enough to account for the speed of the gas whirling around the core of M87.