Online advertising is the means of selling a product on the Internet. With the arrival of the Internet, the business world has become digitalized (数字化) and people prefer buying things online, which is easier and faster. Online advertising is also known as e-advertising. It offers a great variety of services, which can not be offered by any other ways of advertising.
One major benefit of online advertising is the immediate spread of information that is not limited by geography or time. Online advertising can be viewed day and night throughout the world. Besides, it reduces the cost and increases the profit of the company.
Small businesses especially find online advertising cheap and effective. They can focus on their ideal customers and pay very little for the advertisements.
In a word, online advertising is a cheap and effective way of advertising, whose success has so far fully proved its great potential (潜力).

According to .the first, paragraph, buying things online is more ______.

A．convenient
B．fashionable
C．traditional
D．reliable