ABC soup

I forget when was the first time that I drank this soup but it must be when I was extremely young. And I've been wondering why people call this soup as "ABC".

Probably it's because it contains vitamins A, B and C? Or because it's like a rojak, having a little of everything in a pot?
Anyway, hope you'll enjoy it!

Ingredients:
2 large carrots
4 potatoes
4 medium size tomatoes
2 large onions
1 corn (optional)
5 Hong Chou (Red dates) - optional

1) Cut everything into cubes.
2) Put to boil for 2 hours and serve.

Note: Do you know anything about water soluble? My friend told me that carrot needs oil to release its Vitamin A. So, unless you include bones or meat into the soup, it's unlikely that you're going to get Vit.A from the carrots. I do put a few drops of oil into the soup. Don't worry, it tastes good!