[RealJames]

I'd like to add one thing,
to the best of my understanding 牛乳 is cow milk for drinking, like, as you buy it, not straight from the cow, that would be the 3rd one, お乳, or ミルク.
ミルク is anything you'd call milk, that you could theoretically drink, from the tit or commercial or wherever, but not a from a whale for example.

I could be off... there is some drunken advice being thrown at me from across the room.