The ancient Anasazi harvested such native desert vegetation as the purple-flowered bee plant, what they now commonly call wild spinach in northern Arizona and other parts of the southwestern United States.
GWD1-Q30: The ancient Anasazi harvested such native desert vegetation as the purple-flowered bee plant, what they now commonly call wild spinach in northern Arizona and other parts of the southwestern United States. A. what they now commonly call B. a plant that they now commonly call C. now commonly called D. and is mow commonly called E. which it is now commonly called C是个什么成分?
一个在国外论坛上看到的一个GMAT Instructor的解释,大家可以参考一下:
For those who liked E, keep in mind that "which" is a modifier that takes the place of "plant" - essentially "which" is used as a pronoun, so the word "it" is redundant...we're just piling on at that point. You wouldn't say "For Christmas I got a new bike, which it is red". You'd just say "I got a new bike, which is red..."
For A and B, I think it's important to note that "they" does properly replace "Anasazi" as a pronoun...there's nothing wrong with the pronoun itself. What IS wrong here is the logic. We're talking about the ANCIENT Anasazi...so it's illogical that they would "NOW" commonly call a plant something different. Ancient means that there isn't anything they're doing "now". A and B don't really have a pronoun error, but they're both guilty of a vicious logical error.
C is correct - it properly modifies "plant" with "now commonly called", and therefore is correct.
D, just for completeness' sake, illogically makes it sounds like "Anasazi" is now commonly called "Wild spinach" - the word "and" links the two verbs "harvested" and "is", binding them both to the same subject, Anasazi.