Final answer:
Madelyn is eating more salmon because it is a nutritious oily fish rich in omega-3 fatty acids and is safer for pregnant women due to its low mercury content.
Step-by-step explanation:
Madelyn is eating more salmon during her pregnancy because salmon is rich in nutrients that are essential both for her own health and the health of her developing fetus. Salmon is a source of omega-3 fatty acids, which are vital for brain function, growth, and development, and may also help to prevent heart disease and reduce cancer risks.
Additionally, salmon is one of the safer oily fish for pregnant women to consume, as it is low in mercury, unlike other seafood such as swordfish, shark, king mackerel, or tilefish, which are high in mercury due to biomagnification and should be avoided by pregnant women and young children.