This is an example of animals which do periodic migration:

Options

A. Arctic term
B. Elk
C. Whale
D. Locust.

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Migration:**
- Migration refers to the movement of animals from one region to another, often in search of food, breeding grounds, or more favorable environmental conditions.

2. **Define Periodic Migration:**
- Periodic migration is characterized by animals moving to a different area for a short period of time, usually for breeding or seasonal changes.

3. **Evaluate the Options:**
- **Option 1: Arctic Tern** - Known for long-distance migration between breeding and wintering grounds.
- **Option 2: Elk** - Generally migrates seasonally but is not known for periodic migration.
- **Option 3: Whale** - Whales also engage in long migrations between feeding and breeding areas.
- **Option 4: Locust** - Known for periodic migration, particularly during swarming events to find suitable breeding areas.

4. **Identify the Correct Answer:**
- Among the options provided, the locust is the only animal that exhibits periodic migration, as it migrates in swarms to find breeding areas.

5. **Conclusion:**
- The correct answer to the question is **Option 4: Locust**.

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