Sunlight helps our body make Vitamin D. When sunlight touches our skin, it triggers a process that produces Vitamin D, which is very important for strong bones and good health.

Vitamin D helps the body absorb calcium, which is needed for healthy bones and teeth. Without enough Vitamin D, people can have weak bones or diseases like rickets.

Other vitamins like Vitamin C, E, and K come from food and are not made by sunlight.

So, the correct answer is Vitamin D.