No matter where you travel in Asia, you'll find yourself faced with a new culture, amazing food and special and friendly people. Here are some of these wonderful cities.   Beijing, China      Beijing serves as the capital of China. The city is old. In fact, almost all buildings have some cultural or historical significance   --no matter how small they are. Throughout the city you can find temples, palaces, and works of art that can make you breathless.  Siem Reap, Cambodia      The wonderful town of Siem Reap is actually a good place to visit, though most people regard it only as a base point for further trips to Angkor and other nearby attractions. Visitors will be amazed by the beautiful temples and artworks that still exist today.  Kathmandu, Nepal      Located in the heart of the Himalayas, Kathmandu, the largest city and the capital of Nepal, is considered to be one of the most beautiful cities in existence today. It is well-known for its beautiful views of the Himalayas. The shopping districts are world-famous and the hotels in Kathmandu are among the best in the world.  Kyoto, Japan      The city of Kyoto served as the capital of Japan from 794 to 1868. No longer the capital, it is known as the seventh largest city in Japan instead. Kyoto was destroyed many times throughout history by fires and wars. Now the city is home to more than 1.4 million people and presents a modern look to the world. What the cities mentioned above have in common is that they   _  .
all once served as capitals were all destroyed by war once all have many tourist attractions to enjoy all operate under their own laws
Question: No matter where you travel in Asia, you'll find yourself faced with a new culture, amazing food and special and friendly people. Here are some of these wonderful cities.   Beijing, China      Beijing serves as the capital of China. The city is old. In fact, almost all buildings have some cultural or historical significance   --no matter how small they are. Throughout the city you can find temples, palaces, and works of art that can make you breathless.  Siem Reap, Cambodia      The wonderful town of Siem Reap is actually a good place to visit, though most people regard it only as a base point for further trips to Angkor and other nearby attractions. Visitors will be amazed by the beautiful temples and artworks that still exist today.  Kathmandu, Nepal      Located in the heart of the Himalayas, Kathmandu, the largest city and the capital of Nepal, is considered to be one of the most beautiful cities in existence today. It is well-known for its beautiful views of the Himalayas. The shopping districts are world-famous and the hotels in Kathmandu are among the best in the world.  Kyoto, Japan      The city of Kyoto served as the capital of Japan from 794 to 1868. No longer the capital, it is known as the seventh largest city in Japan instead. Kyoto was destroyed many times throughout history by fires and wars. Now the city is home to more than 1.4 million people and presents a modern look to the world. What the cities mentioned above have in common is that they   _  .
A. all once served as capitals
B. were all destroyed by war once
C. all have many tourist attractions to enjoy
D. all operate under their own laws
Answer: