Please choose the correct ending to complete the given sentence: Health: [header] How to build up your immune system before surgery [title] Follow a balanced, healthy diet. [step] Vitamin a can boost your immunity while reducing the risk for infection. You should look for foods that are high in this nutrient.

Ending1: Keep fruit, vegetables, and lean meats fresh and lean, like chicken, fish, and crab. Keep sunflower seeds on your diet as well, as they can help to prevent reye's syndrome. Ending2: Foods that are rich in protein include canola oil, chicken, fish, and nuts. [substeps] Eat enough fish to help support your immune system. Ending3: This includes : [substeps] Carrots sweet potatoes pumpkin squash beef liver beans [title] Find foods rich in vitamin a. [step] Vitamin c is another important vitamin for immunity, but you can get enough of it from your diet without having to take a supplement. Ending4: Eat an amount of it every day: oranges, grapefruit, broccoli, walnuts, and beans, and avoid any things high in added sugar or high carbohydrates. [substeps] You can also go for ground nuts as a source of protein.

Answer format: ending1/ending2/ending3/ending4