Final answer:
The nurse will recognize effective teaching when the client states the need to increase the intake of iron-rich foods, as adequate nutrition including iron is essential during pregnancy to support the growing fetus.
Step-by-step explanation:
The nurse at the prenatal clinic would determine the teaching effective if the client makes the statement: "I need to increase my intake of iron-rich foods." This is because during pregnancy, especially in the second and third trimesters, the demand for nutrients increases to support the growing fetus. Adequate intake of nutrients such as iron, folic acid, calcium, and omega-3 fatty acids is crucial. The claim that a pregnant woman needs to avoid all fats or limit fluid intake is incorrect, as fats are an essential part of a healthy diet and adequate hydration is important. Additionally, skipping meals is discouraged because it can lead to insufficient nutrient intake for both mother and fetus.