Step 1: Understanding natural disasters
- Natural disasters are catastrophic events caused by natural forces such as earthquakes, floods, hurricanes, and tsunamis. These events cause significant damage to the environment, property, and human lives.
Step 2: Analyzing the options
- (A) Flood: Floods are a natural disaster caused by excessive rainfall, leading to the overflow of water bodies and inundation of land.
- (B) Drought: Drought is a prolonged period of abnormally low rainfall that results in water shortages, making it a natural disaster.
- (C) Tsunami: Tsunamis are large sea waves caused by underwater earthquakes or volcanic eruptions, and they are classified as natural disasters.
- (D) Electric crisis: An electric crisis is a man-made issue related to the failure of electricity generation or distribution systems, not a natural disaster.
Step 3: Conclusion
Thus, the correct answer is (D) Electric crisis, as it is not a natural disaster but rather a technological or infrastructure issue.
\[
\boxed{\text{Correct Answer: (D) Electric crisis}}
\]