单项选择题

According to the German researchers, the energy source at the center of the Milky Way Galaxy ______.

A．has been covered up by vast clouds of dust and gas
B．still remains unknown to astronomers
C．has proved to be a black hole
D．actually provides power for the rotation of file great spiral of stars

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热门试题

单项选择题The novel is structured around the discovery of the hero's origin. The novel probably refers to ______.

A．Wuthering Heights
B．History of Tom Johns, a Foundling
C．David Copperfield
D．Gulliver’s Travel

单项选择题You can find the Grand Canyon in the State of ______.

A．Arizona
B．California
C．New Mexico
D．Texas

单项选择题______ is the capital city of Scotland.

A．Dublin
B．Edinburgh
C．Cardiff
D．New Castle

单项选择题Which of the following words can be used to connect two clauses in a coordinate sentence

A．Through.
B．When.
C．But.
D．If.

单项选择题______ was considered to be the greatest dramatist in the 18 century in British lime.

A．Henry Fielding
B．Laurence Sterne
C．Oliver Goldsmith
D．Richard B. Sheridan