Select from:
1). oceans
2). wetland
3). rivers
4). water
5). streams
6). trees
7). fog
8). vegetation
Q: You are presented with the quiz "If fossils of a fish are found in a place then that place used to be covered by what in the past." But you don't know the answer, so you turn to your teacher to ask for hints. He says that "if fossils of a water animal or plant are found in a place then that place used to be covered by water in the past" and "fish are a diverse group of animals that live and breathe in water". So, what's the best answer to the question?
A:
4).