I can't put my finger on it, but when I was reading the original sentence, the English seemed awkward. In any event, the question does test one's ability to judge singular or plural verb tense.
First things first, what is the subject of this sentence? Really, that in itself is half the battle if not more in solving this SC. Is it
A new species of geese which requires an
is or only geese which would take an
are? I'm not too sure if there is an absolute rule to this but simply reading the sentence gives the impression we are talking about the habits of a species. Also, I think there is a tendency for the entire compound phrase (is that the term?)
new species of geese to be first considered the subject of the sentence. Use some good ol' common sense to judge which one makes more sense.
A. A new species of geese, which is discovered near the North Canadian River, are monogamous, live in permanent pairs, and are dominant
A new species of geese.... is....
are is wrong!
B. A new species of geese, discovered near the North Canadian River, are monogamous, living in permanent pairs, and dominant
Wrong for the same reason as (A)
C. A new species of geese, which are discovered near the North Canadian River, are monogamous, live in permanent pairs, and are dominant
Wrong for the same reason as (A)
D. A new species of geese, which is discovered near the North Canadian River, is monogamous, live in permanent pairs, and are dominant
A new species of geese... is... Ok, good. We got that sorted. But what else should we be looking at? Ah, a bit of parallelism awkwardness. The last part
are dominant throws us right back to square one. Eliminate.
E. A species of geese newly discovered near the North Canadian River is monogamous, lives in permanent pairs, and is dominant
Bingo! A species of geese...is... lives..and is... Everything looks good and we're done!