Which of the following is an example of natural selection?

A
Over time, the Earth’s crust started to solidify about one-billion years after the planet was formed.

B
Over time, a species of cricket became green because green crickets were better able to hide among the leaves.

C
In the winter, as food becomes more scarce, some species of birds fly to new habitats in the south.

D
In June, the Northern Hemisphere gets more direct sunlight due to the tilt of Earth’s axis as it revolves around the sun.