A common example of stem tuber is:

Correct option is D

The correct answer is: (d) Potato
Explanation
· A stem tuber is a swollen underground stem that stores food.
· Potato is the most common example of a stem tuber.
· It has nodes (eyes) from which new shoots grow — a key feature of stems.
Why the others are incorrect:
· Onion → bulb (modified leaf)
· Garlic → bulb
· Ginger → rhizome (an underground stem, but not a tuber)
Thus, the correct example of a stem tuber is potato.
Additional Information
· Other examples of stem tubers: yam, artichoke.
· Potato tubers store starch and help in vegetative propagation.