All of the following are considered good sources of Vitamin D except?

Vitamin D is a crucial nutrient that plays a vital role in maintaining healthy bones and immune function. When examining the sources of Vitamin D, it's important to recognize which foods are naturally rich in this vitamin or have been fortified with it.

Salmon, egg yolks, and fortified milk are all recognized as good sources of Vitamin D. Salmon, a fatty fish, provides a significant amount of Vitamin D, along with healthy omega-3 fatty acids. Egg yolks also contain some Vitamin D, albeit in smaller amounts compared to fatty fish. Fortified milk is a common dietary source of Vitamin D, as manufacturers often add it to enhance nutritional value.

In contrast, avocados do not provide a significant amount of Vitamin D. They are indeed nutrient-dense, offering healthy fats, fiber, and a variety of vitamins and minerals, but they lack Vitamin D content, either naturally or through fortification. This differentiating factor is why the identification of avocado as the exception in this context is accurate.