Please answer the following question: Read the following article and select the best answer. Article: Hong Kong, major commercial center for Asia, and with a population which has grown at an alarming rate to over 5 million, is a city highly dependent on mass (, ) transit of all sorts, both local and long distance. An ordinary Hong Kong worker or businessman, going about his daily activities, simply must use transportation at one time or another. Because Hong Kong is in two parts, Kowloon, on the mainland side, and Hong Kong, the island, with Hong Kong's harbor in between Hong Kong's mass transit systems, in addition to going over land they must also cross water. Going from home to work, or going shopping from one side of the harbor to the other, the Hong Kong resident has three choices. One way is to take a bus which will cross the harbor through an under water traffic tunnel moving slowly through bumper- to-bumper traffic.Another way is by ferry boat , a pleasant ride which crosses the harbor in from seven to fifteen minutes. But by far the fastest way of crossing the harbor is the newly built underground electric railway, the Hong Kong Metro . If one gets on the train in the Central District,the commercial area of Hong Kong on the island side, he can speed across the harbor in an astonishing three minutes. On the other side of the harbor the railway continues, snaking back and forth through the outlying districts of Kowloon, allowing one to get off a short distance from his destination. The story of the Metro is an encouraging one for supporters of mass transit. Although building the system was certainly a challenging task, the Japanese firm hired to construct it did so in record time. Construction got underway in 1979 and it was completed in 1980. For the average commuter the system has only one disadvantage; it is more expensive than by bus or ferry. One can ride the bus across the harbor for half as much or he can ride the ferry across for less than one-fifth as much. Question: The business area on the island side of Hong Kong is referred to as _ . - Kowloon - the Central District - the Hong Kong Metro - downtown Hong Kong
Answer:
the Central District