Answer: B Tsunamis
Explanation: tsunami is generated by displacement of large volume of water which the causes of the displacement can be earthquake, volcanoes, landslide and other underwater explosion. Tsunami is refered to as tidal waves
The name for such a hole is "caldera" which is a word of Spanish origin meaning "a pot" or a "cooking pot" (thing of cauldron!) - and this word is used because it resembles the shape of this hole.
Often the Calderas are filled with water forming lakes and often there is an island in the middle of the water.
Despite Hong Kong historically being part of China and being inhabited by Chinese people, that drastically happened in the last century. Hong Kong got into the hands of the European colonial powers, and even after they left the area, they didn't left Hong Kong. The reason why the presence in Hong Kong was kept was because of its excellent strategic position.
The newly formed nation had excellent ports and excellent location. It was quickly industrialized. That led to rapid economic growth. The economic growth and the prosperity of the small nation made, as well as it deep connections with the Western World, attracted lot of people to move in it. The Chinese population is still dominant, but over time people from all over the world moved in, thus the ethnic structure of this nation changes significantly, to a point where now it has citizens from pretty much every corner of the world.
CA air mass invades the religion