The rugged terrain, the fossils of large mammals, and the herd of bison are three things that would make Serena believe she was having a real adventure.
Serena wasn't finding the trip exciting, but her friend claimed that they could have a lot of adventures there. She couldn't believe it, but when she heard about the rough terrain, the existence of fossils and when she saw a herd of bison, she believed her friend was telling the truth.
This question is about the story "The Adventure Begins."
Learn more about fossils at the link:
https://brainly.com/question/2257012
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