Organisms must have variation within a population in order for natural selection to occur. Which situation is an example of this variation?

1. A frog living in a pond is eaten by a predator, while others in the same population survive.

2. A snake living in a desert produces more offspring than other snakes in the same population.

3. Some rabbits living in a forest have short, spotted ears, while others have long white ears.

4. Some birds living in a grassland eat less than other birds who eat the same food.