Explanation:

Let’s break it down:

- Wisdom teeth (Option 1)

These are the classic vestigial organs in humans. Our ancestors needed them for a rougher diet, but today, most people don’t use them, and they often just cause trouble.

- Spleen (Option 2)

The spleen’s far from useless. It’s important for your immune system and filters blood.

- Thyroid (Option 3)

This gland controls your metabolism and many other processes. Definitely not vestigial.

- Gall bladder (Option 4)

The gallbladder stores bile to help digest fats. Humans can live without it, but it isn’t considered vestigial.

So, option 1—wisdom teeth—is the right pick. Good call.