Common potatoes and sweet potatoes are both edible roots. Roots of varieties grown for food have orange flesh.

The Edible Root:
The edible root among the given options is the radish. Let's explore why radish is considered an edible root.

Definition of Edible Root:
An edible root is a part of a plant that grows underground and can be consumed as food. Edible roots are rich in nutrients and are commonly used in various culinary preparations.

Explanation:
Here's why radish is considered an edible root:

1. Radish:
- Radish is a root vegetable that belongs to the Brassicaceae family.
- The edible part of the radish is its swollen taproot, which grows underground.
- Radishes come in various shapes, sizes, and colors, such as red, white, purple, or black.
- They have a crisp texture and a slightly spicy or peppery flavor.
- Radishes are often consumed raw in salads or used as a garnish.
- They can also be cooked and added to stir-fries, soups, or stews.

Other Options:
- Potato: The potato is a starchy tuber, not a root. It grows underground but is part of the stem of the plant. Therefore, it is not considered an edible root.
- Pineapple: Pineapple is a tropical fruit that does not grow underground. It is the fruit of a plant and not an edible root.
- Cabbage: Cabbage is a leafy vegetable that grows above ground. It does not have an edible root.

Conclusion:
Among the given options, the only edible root is the radish. It is a root vegetable with a swollen taproot that grows underground. Radishes are consumed raw or cooked and are known for their crisp texture and slightly spicy flavor.