The Term Two-Party System Is Applied to the UK for All

The term two-party system is applied to the UK for all the following reasons EXCEPT

A) from 1945 to 2010, only leaders of the Conservative or the Labour Party served as prime ministers.
B) Conservative or Labour candidates come in first or second in virtually every parliamentary contest throughout the UK.
C) since 1945, the Conservative and Labour parties have routinely divided at least 85 percent of the seats in the Commons.
D) between 1945 and 2005, the Conservative and Labour parties have won roughly the same number of general elections.
E) only two political parties are allowed under British law.