Step 1: Understanding the Concept:
Some plants store food in modified stems.
Others store in modified roots.
Step 2: Key Modifications:
• Modified stems: Potato (tuber), Onion (bulb), Ginger (rhizome).
• Modified roots: Carrot, Radish, Sweet potato.
Step 3: Analyzing the Options:
• (A) Carrot - Radish: Both are modified roots.
• (B) Onion - Radish: Onion is a modified stem, but Radish is a modified root.
• (C) Sweet potato - Potato: Sweet potato is a modified root, Potato is a modified stem.
• (D) Potato - Onion: Both are modified stems.
Step 4: Final Answer:
Therefore, option (D) is correct.