StaceyKoprince Wrote:Tough one! Let's first cut this down to the core:
By <a time in the past>, A. had built an X so large that only A, B, and C...
First, there's an idiom. A, B, and C rival X for <some attributes>. If you want to use rival in verb form, you just put the X right after (or a pronoun referring to X, as in this case) and you use the preposition "for" to introduce what the attributes are.
D changes the form of the word rival - now it's a noun. A, B, and C could be X's rivals in their scale and magnificence. Again, idiom issue. You could say that A, B, and C are the primary rivals of X, but you wouldn't present the attributes by which they rival X with the preposition "in." You'd say something like "A, B, and C are the primary rivals of X based upon <some attributes>." (Note: there are other words you could use besides "based upon" - eg, "due to." But not "in.")
about
Rival sb in/for some acpect:
i have search in Longman, there are some sentence can support
Rival sb in XX, which is also listed as a idiom.
1#The weathermen said the storm had rivalled summer hurricanes
in its intensity.
2#The prince built a vast palace, rivalling Versailles
in size and opulence.
Unfortunately, i can't find material that can support
Rival sb for XX, except when
Rival is used as
Noun.
Stephen is Ron's rival for the job---Stenpen and Ron both need job, so we use 'for'.
i don't know what's wrong with D, which is really like 1# above. although i try several dictionnary, i can't find the usage of "rival [Vt] for". SO:
1# is A really better than--or just shorter than-- D?
2# are there some dictionaries that deserve recommendation for listing lots of idiom tested by GMAT?
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if A is the right key, there could be only one explanation:
X rival Y in(for) Z IS DIFFERENT FROM X is a rival of Y in(for) Z.
Ron,
may be some intructors can be your rivals in teaching GMAT, but no one can rival you. Haha!