Fossils of the arm of a sloth found in Puerto Rico in 1991,

Question

Fossils of the arm of a  sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of  the Greater Antilles islands.

(A) sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

(B) sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on

(C) sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of

(D) sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

(E) sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

rthothad · Answer

I would go with 'C' but I am not sure about the phrase 'making  this  the earliest known mammal'

pb_india · Answer

"D" my pick.
Mammal on sounds better than mammal of

HongHu · Answer

A: Sounds like the sloth was found in Puerto Rico in 1991, and was dated at 34 million years old. Wrong
B: Fossils of the arm of a sloth, ..., has been dated at 34 million years old, thus making it the earliest mammal known ... "It" refers to the subject of the sentence, which is wrong. Also fossils is plural, can't use "has".
C: Same thing, "was" is wrong, "this" is not clear.
D: Correct
E: "was" is wrong, also sound like the sloth was 34 million years old.

(E)
Edit, I meant (D)

MA · Answer

D for me because the subject of the sentence is fossils and the subject-fossils- requires plural verb have been dated............

HSWKM · Answer

Yes it is D. 

"fossils..........have been"

chunjuwu · Answer

Thanks 

the OA is D.

vprabhala · Answer

D... fossils plural..so "have been" is justified..

doloris · Answer

can some one please tell me which book is being used for these questions?

: such as the one posted here.SC0628

Fossils of the arm of a sloth found in Puerto Rico in 1991,

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