Fact 1: Many corals secrete an exoskeleton that builds up to become a coral reef. Fact 2: To fisherfolk, coral reefs are homes to fish that are waiting to be caught. Given the two facts above, what do exoskeletons secreted by corals do?
pick from the following. 1). Give homes to humans. 2). Give homes to penguins. 3). competing for resources. 4). Give homes to fish. 5). reproduce. 6). Give homes to birds. 7). preventing heat transfer. 8). protect them.
Answer:
4).