So this city blonde goes to a barn.

She asks the farmer: “Excuse me, why does that cow have no horns?”.

The farmer, being quite the expert on the matter, explained to her with great detail:

“Well ma’am, there’s many reasons why some cows don’t have horns. Some breeds don’t have horns. For example, Angus cows don’t have horns. Another reason is that when you’ve been milking a cow for too long, their horns get very sensitive, so we remove them in a process that’s completely painless to the animal. And sometimes, when they’re calves, we don’t want them to grow horns so we put a little acid where the horns would grow and they never grow horns.

But the reason why THAT cow doesn’t have horns is that it’s a horse”.