Question

Identify the incorrect statement.

• A. A tsunami is a series of waves generated when water in a lake or the sea is rapidly displaced on a massive scale.
• B. A tsunami is an after-effect of an earthquake on the seabed.
• C. A tsunami has smaller amplitude (wave height) offshore and a very long wavelength.
• D. None of the above.

Answer 1

The Correct Option is D

Step 1: Read all the statements carefully
1. A tsunami is a series of waves generated when water in a lake or the sea is rapidly displaced on a massive scale.
2. A tsunami is an after-effect of an earthquake on the seabed.
3. A tsunami has smaller amplitude (wave height) offshore and a very long wavelength.
4. None of the above.

Step 2: Check each statement
- Statement 1: This is correct. A tsunami is indeed a series of waves caused by sudden displacement of water, usually in oceans but sometimes in lakes, due to seismic or volcanic activity.

- Statement 2: This is also correct. Most tsunamis are generated by undersea earthquakes that displace large volumes of water on the seabed.

- Statement 3: Correct as well. Tsunamis in the open sea have very long wavelengths (hundreds of kilometers) and small amplitude, which makes them less noticeable offshore. As they approach shallow coastal waters, the wave height increases dramatically.

Step 3: Interpret option 4
Since all the first three statements are scientifically correct, the option that says "None of the above" is the right answer to indicate that none of the earlier statements are incorrect.

Final Answer: The correct option is (D) None of the above.