To build a healthy plate, the best approach among the given options is to vary your protein choices. This ensures you are getting a wide range of nutrients, amino acids, and benefits from different sources of protein, such as beans, lentils, fish, poultry, nuts, and dairy.
While drinking whole milk can be a good source of calcium, it is important to consider other sources as well, and "whole milk" may not be suitable for everyone, particularly those watching their fat intake.
Eating at least half white grain breads and cereals is generally not recommended for a healthy diet; instead, it is better to focus on whole grains, which are more nutrient-dense and provide more fiber.
In summary, varying your protein sources is the most beneficial choice for creating a healthy plate.