Final answer:
Spinach is the best choice for adding to the diet of a patient with folic acid deficiency anemia due to its high folic acid content. Other beneficial folic acid-rich foods include liver, beans, seeds, nuts, and organ meats.
Step-by-step explanation:
The best food to add to the diet for a patient with anemia caused by folic acid deficiency would be spinach (a). Spinach is a dark green leafy vegetable that is rich in folic acid, a nutrient essential for the formation of red blood cells. Other foods high in folic acid include liver, beans, seeds, nuts, and organ meats. It's important for patients with anemia to consume sufficient amounts of folic acid to prevent megaloblastic anemia, which involves a deficiency of vitamin B12 and/or folate.