2. Egg with yellow yolk
These are the eggs that come from factory chicken. These chickens do not receive enough sun light, ventilation, space and they are only fed with grains. There are lot of filths on the floors and they have been hatched from incubators, which is not very good.
3. Egg with light yellow orange yolk
These eggs come from large chicken farms, whose conditions are not that bad as factories. These eggs are not that healthy as first one because they are fed only with grains. But relatively these eggs are easy to find from local groceries and healthier than the ones you bought from super markets.
So, try to add the best eggs for your meals.