The question asks about the duration of destruction for a significant number of houses during an earthquake.
The options provided are: A. 30 minutes, B. 30 seconds, C. 40 seconds.
Earthquakes are sudden and violent events. The seismic waves that cause destruction travel rapidly. While an earthquake can last for a minute or two, the most intense shaking, which causes the most damage, often occurs over a much shorter period. Ruining 90,000 houses would likely happen during the peak of the seismic activity.