阅读下面短文，从短文后各题所给的四个选项A、B、C、D中，选出可以填入空白处的最佳选项.
Football is, I suppose, the most popular games in England. One had only to go to one of the important
31 to see this. One can see kinds of people there, shouting and
32 for one side or the other.
One of the most
33 thing about football in England to a stranger is the
__34__ knowledge of the game which even the
35 seems to have. He can tell you the names of the players in
36 of the important teams. He
37 photos of them and knows the result of large numbers of matches. He will tell you
38 he expects will win such and such a match,
39 his opinion is usually as
40 as that of men three or four times his
41 .
Most schools in England take
42 seriously—much more seriously than nearly all the schools in other countries,
43 lessons are all important and games are left for one’s own arrangements（安排）. In England, it is believed that
44 is not only a matter of filling a boy’s mind with facts in the
45 ; it also means character training; and one of the
46 ways of training character is by means of games,
47 team games, where the boy has to learn to
48 with others for his team, instead of working just for himself alone. The school therefore arranges games and matches for its
49 . Football is a good team game and it is good exercise for
50 .
（2009?湖北模拟）一束包含a、b两种不同频率的光，照射到金属板MN上O点，其中a光能使金属板发生光电效应，现在MN板前放一两面平行的玻璃砖，结果光束被分成与入射光平行的两束出射光，分别射到P、Q两点，如图所示，则（ ）
