Science Assessment

According to the theory of natural selection, what happens to organisms of the same species when a major change occurs in their environment (for example, the amount of rainfall decreases or the temperature increases)?

1. The individual organisms that already have traits better suited for the changed environment would be more likely to survive and reproduce, and those that do not have those traits would be less likely to survive and reproduce.
2. All of the individual organisms would try to develop new traits so that they could survive in the changed environment.
3. Some of the individual organisms would try to develop new traits so that they could survive, and the other organisms would die.
4. Because all organisms of the same species have the same traits, one organism would never have an advantage over another of its species.  They would either all survive, or they would go extinct.