Quote:
B. satellites, which is a part of a 15-year effort to subject how Earth's atmosphere, oceans, and land surfaces interact
(B) has a similar subject-verb agreement problem as (A): “…one of the many satellites, which
is part of…” Again, that doesn’t make much sense, since ALL of the satellites are part of the effort, so we need a plural verb.
And this is a very minor thing, but I don’t love the use of “which” here in general.
Modifiers beginning with “which” are non-essential modifiers, meaning that the modifier isn’t strictly necessary for us to grasp the meaning of the sentence.
But I think we DO need the modifier (“that are part of a 15-year effort…”) in order to understand exactly which satellites we’re talking about.
I don’t think that the difference between “which” (non-essential modifier) and “that” (essential modifier) has ever been the deciding factor on an official SC question, but it gives us an extra reason to get rid of (B).
Quote:
C. satellites, part of 15 years effort of subjecting how Earth's atmosphere, oceans, and land surfaces are interacting
As in (B), there’s a subtle problem with a non-essential modifier: “…one of the many new satellites, part of 15 years effort…”
That’s not WRONG, exactly, but it turns the description of the satellites into an incidental, non-essential modifier. It makes more sense to say “… one of the many new satellites THAT are part of a 15-year effort…”
And just like in (A), we have that goofy little phrases “15 years effort” and “effort of subjecting.” See the explanation of (A) for more on these two issues.
Finally, there’s no good reason for the verb tense at the end of the underlined portion: “are interacting” (present progressive tense, if you’re a fan of grammar jargon) emphasizes the fact that the interactions are happening right now, and there’s no real reason to do that. As we’ll see in a moment, there are more elegant ways to phrase this without using an unnecessarily complex verb tense.
So (C) is out.
Let’s line up the last two side-by-side to make it easier to see the differences:
Thanks for the nice explanation.
B.
C.
are just important part of the sentence, but they are kept with non-essential modifier! So, can we cancel choice B and C as the important parts are kept with 'non-essential' modifier?