在IEnumerable集合中查找所有依赖子项的最佳方法是什么

public class Item
{
    public string Name { get; set; }
    public List<Item> Dependencies { get; set; }
}

public List<Item> FindDependentItems(Item item)
{
    List<Item> dependentItems = new List<Item>();

    if (item.Dependencies != null && item.Dependencies.Count > 0)
    {
        foreach (var dependency in item.Dependencies)
        {
            dependentItems.Add(dependency);
            dependentItems.AddRange(FindDependentItems(dependency));
        }
    }

    return dependentItems;
}

Item item1 = new Item { Name = "Item 1" };
Item item2 = new Item { Name = "Item 2" };
Item item3 = new Item { Name = "Item 3" };
Item item4 = new Item { Name = "Item 4" };

item1.Dependencies = new List<Item> { item2, item3 };
item2.Dependencies = new List<Item> { item4 };

List<Item> items = new List<Item> { item1, item2, item3, item4 };

List<Item> dependentItems = FindDependentItems(item1);