请教gwd-13-28

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.

1. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

2. 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

3. sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of

4. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

5. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

感觉答案都不对，D中的主句是被动语态，以前看到人总结过，被动式一般不用现在分词伴随或结果状语，感觉比较怪