请教几个PP语法？

xlsh

各位大侠，本人是新手，做PPREVIEW时发现有好些不明白之处，请各位出手相助。多谢多谢！


1，Spurred by the phenomental growth of the city of Chicago after the Civil war, Illinois became  ?
A, that a major industrial state;  B,  to a major industrial state;
C, a major industrial state;  D,  to be a major industrial state.
答案是D， 但是C 有可能也对吗？   

2，[Identical ]twins are always [of the] same sex, [resemblance] one another very [closely], and have similar fingerprints and blood groups.      
答案是C， 应该怎么改？为什么不是B？

3，Working [by] chemical reaction, and being [independence] of atmospheric oxygen, rockets are used [to power] interplanetary [space] vehicles.
答案是B，为什么不是A，应该怎么改？  

4,Oak trees furnish more [timber annually] in the U.S. than [any of] other broad-leaved tree and are [second only] to conifers [in tota]l lumber production.
答案是B， 为什么不是C（the second ）？应该怎么改？

5, Intricate [choreographer] emphasized the beauty and virtuosity [of the ]  nineteenth-century prima ballerina, while the male [dancer functioned] only as her partner [until] the twentieth century.
答案是A，怎么改？为什么不是B？

6， The New York City Ballet has been  ?  of United States classical ballet companies since its inception in 1946.
A, the consistently creative most;  B, consistently creative the most;
C, most creative the consistently;  D, the most consistently creative.
答案是B， 为什么，怎么翻译？

谢谢！