单项选择题

A young man gazes intently at his mobile device, to which he is listening through earphones. He is so engrossed in his film, his television show, his computer game or whatever he is watching that he does not notice he is blocking the door of the train. Other passengers glare at him. "Do it at home," counsels the bright yellow poster on the Tokyo metro.
In 2009 some 43 % of Japan’s population watched TV on mobile phones. It is the only country apart from South Korea where the platform has become commonplace. But mobile television in Japan is not all that mobile. When broadcasts began in 2005, people were expected to use their toys to while away long commute by train or to kill time while waiting for the bus.^① Instead they mostly choose to play with them at home.
Imagine a teenage girl who wants to watch an episode of her favourite soap opera. The living-room television is being monopolised by her father, who is watching sport. Her brother is using the computer. What does she do If she is an American, living in a reasonably affluent household, she simply switches on another television. There is probably one in her bedroom. If she is South Korean or Japanese, on the other hand, she is more likely to live in a high-rise flat with only one set. She settles down in her tiny bedroom, pulls a mobile phone out of her pocket and turns it on. The screen is small but adequate.
When asked why people watch mobile television in their homes, Japanese and South Korean media executives tend to make the same gesture. They clutch their mobile phone to their chests, signifying "mine". The appeal of mobile television is not so much that it is portable but that it is personal. When it proves impossible to reach agreement with other television-watchers in a household, mobile TV is a reasonable fall-back option. ^② It is also a dismal business.
In both Japan and South Korea practically everybody gets their mobile television free. The service was supposed to be supported by advertising, but the prop is weak. Although many Japanese and South Koreans watch television on their phones, they tend to do so briefly and erratically, so programmes often attract small audiences. ^③If mobile TV is not used enough to make money from advertising, it is also not essential enough to persuade lots of people to pay.
Even before it catches on elsewhere, mobile television is failing in the two countries where it seemed most likely to succeed. The experience of Japan and South Korea suggests that people will watch TV on tiny screens if they have to. But those countries also provide a reminder that popularity does not always translate into business success. Old-fashioned TV wins again.
We can draw the conclusion from Paragraph 3 that the popularity of mobile televisions______.