Which statement about the levels of organization in anatomy and physiology is most correct.

• A. To understand any other level, you must be an expert in atoms & molecules because they are the most basic. 
• B. The molecular and organ system levels are most closely related.
• C. Changes to anatomy or physiology at one level are likely to affect function at many other levels.
• D. People who study whole organ systems are unlikely to need to understand the behavior of atoms.