【单选题】

We can learn from what P. S. Tregidgo once said that ______ .
A．if there are parties in Britain, none of them will be strong enough to have control in the government

B．the more parties there are, the more likely it is that they will have the decisive say in the government
C．the two party system contributes to the establishment of a powerful and long lasting government
D．if there are only two parties in Britain, it will be easy for the government to control them