Final answer:
The family physician needs to know the patient's dietary habits and medical history in order to influence them about nutrition.
Step-by-step explanation:
The aspect of the patient that the family physician needs to know in order to influence their patients about nutrition is d) Dietary habits and medical history. By understanding the patient's dietary habits, the physician can assess the current nutritional intake and identify areas that need improvement. Additionally, knowing the patient's medical history is important to take into account any pre-existing conditions or medications that may impact their nutritional needs.