In 2010, 700 million people huddled together in front of their television sets to watch the World Cup final between the Netherlands and Spain. Even more are expected to tune in to this year's contest, which kicks off on June 12th with a match between Brazil and Croatia in Sao Paulo. Brazil are the runaway favourites to win the tournament, with bookmakers offering odds of less than three to one on the home team winning the championship．Many experts agree that the country will benefit from a strong home advantage, as local crowds roar on the Seleqao．How much does playing on home turf fealty affect a team's performance?
Sports scientists have come up with all sorts of theories to explain why playing at home helps. In 2007 a study investigated the influence of crowd noise on referees in the English football Premier League. It showed that some were more likely to flash yellow cards and award penalties against touring players than the hosts, because they relied on the split-second rise in the home crowd's roar as a reminder to determine if a tackle deserved punishment. In the most recent season of the Spanish football Riga, two-thirds of all penalty kicks were awarded to the home team.
In the latest English football season, the top 20 clubs enjoyed a home success rate of 50%, while their victory rate on the road was 32%. In 12 of the past 19 World Cups the host nation has made it to the semi-finals and six times it has gone on to win. The effect can be seen in other sports too．  A Before the start of the London Olympics in 2012, UK Sport, a government agency, studied the results of more than 100 big tournaments across 14 Olympic sports.  B  As it turned out, Britain bettered its 2008 performance by winning 18 more medals（10 of them gold), an improvement of 38% . C  At the Beijing games, China won 59% more medals than it had done at the 2004 Athens games.   D Russia topped the medal table in Sochi：in the previous winter Olympics it had come sixth．
Given these numbers, it is not surprising that teams have poured money into maximizing their home advantage. For example, Brazil has spent a considerable fortune on, if somewhat leisurely, a programme of stadium construction and renovation. In all its home advantage is worth the equivalent of a 0.6-goal headstart in every match, according to Goldman Sachs, an investment bank. Like most others, Goldman predicts that Brazil will triumph this year. Other countries' fans will have to hope for a miracle-and perhaps bid to stage the Cup on their own home turf next time.
What does "some" in Paragraph 2 refer to?

A．Crowd noises.	B．Referees.
C．Touring players.	D．Host players.

Put the following sentence in the most appropriate place marked A, B, C, or D It predicted that the London home advantage would boost Britain's medal haul by as much as 25％．
What can be inferred from the passage?

A．Fans may raise their noise levels to cheer their teams up.

B．Brazil will win because of its strong ability.

C．It is a waste of time and effort for countries to hold sports games.

D．The visiting teams have a good chance of winning.