Final answer:
Earthworms sense movement and light through their skin, utilizing a simpler brain to process sensory information.
Step-by-step explanation:
Earthworms use their skin to sense movement and light. They do not have eyes, ears, or a nose as humans do. Instead, they have a sensitivity to light and vibrations in the environment through their skin. While some other kinds of worms, like flatworms, have eyespots that can detect light, earthworms rely on their skin for these sensations. Their brains, although simpler compared to human brains, are capable of processing this sensory information and allow the earthworms to respond accordingly.