Sentence 3 should be revised to correct a misplaced modifier issue. The sentence reads: "The bird-hipped dinosaur group consisted of herbivores such as Stegosaurus." The phrase "such as Stegosaurus" is placed incorrectly, as it suggests that Stegosaurus is an example of the entire bird-hipped dinosaur group, which is not the intended meaning.
A possible revision could be: "Herbivores like Stegosaurus belonged to the bird-hipped dinosaur group." This revision clarifies that Stegosaurus is an example of the herbivores within the group rather than the entire group itself.