请阅读Passage2。完成第小题。 Passage 2 The World Cup has become the most streamed live sporting event the US has ever seen, as Americans tuned in to this year's tournament on their smart phones, tablets and computers in record numbers. A surge of US interest in football this year has also led to record television audiences for broadcasts on ESPN and Uni-vision, the Spanish-language network. The US team's loss on Tuesday to Belgium averaged a 9.6 overnight rating on ESPN, according to Nielsen, the highest for any World Cup match the network has broadcast. But a 50 per cent surge in live streaming compared with the previous record, set during the 2012 London Olympics, shows that the sport's appeal has grown particularly among younger, more digital, fans. Young people are energetic and fond of sporting, The World Cup is a great tournament of football, so they must be attractive. On the other hand, now the electronic devices are developing rapidly, more people have smart phones, tablets and computers. Then to watch the World Cup becomes much easier. US viewers have so far watched nearly 30m hours of streaming video on ESPN's WoAd Cup website and apps, the network said, beating the previous record of 20.4m viewing hours during NBC's 2012 Olympics coverage. Univision has streamed 1.Sm hours since the start of the tournament. Last week's USA vs. Germany match drew a record 1.Tm streaming viewers to ESPN at its peak, with streaming on Univision peaking at 747,000. Tuesday's USA vs. Belgium match peaked at 1.5m streams on ESPN and 680,000 on Univision. In comparison, live streaming of January's Super Bowl peaked at l.lm. While the elimination of the US team leaves a question mark over US fans' interest in the rest of the tournament, Univision's audience for non-US games has been robust. Univision said its broadcast on Sunday of the Mexico vs. Netherlands match was the most-watched programme, of any kind, in US Spanish-language TV history, with an average 10.4m viewers. Its audiences have been the largest in cities with large Spanish-speaking populations, such as Miami, Los Angeles, Houston and New York. With most matches being shown during business hours, Americans are increasingly turning to their devices, such as smart phones, tablets and computers to keep up with the tournament. Fifa,football's governing body, said US fans make up 20 percent of its global digital audience and are spending more time on its website and apps than fans in Brazil, Germany, England and France combined. With different kind of electronic devices to watch World Cup, the number of audience becomes larger. The flood of demand caused some problems with ESPN's feeds, leading frustrated viewers to take to Twitter to complain about the match cutting out. That had also happened during the USA vs. Germany game. The word "surge" (Line 1, Para. 2) may mean__________. 查看材料
A．a sudden increase B．an unexpected decrease C．an abrupt change D．a high wave