According to the Dietary Guidelines for Americans, the most relevant option to maintain a healthy weight and get the nutrients your body needs is:
B. Balanced calories eating with activity level.
This emphasizes the importance of balancing the calories consumed through food and beverages with the calories expended through physical activity. Additionally, choosing nutrient-dense foods (though not specifically listed in your options) is also crucial for meeting nutritional needs while managing weight effectively.
While washing hands when preparing food is important for food safety, it doesn't directly relate to maintaining healthy weight or nutrient intake.