Until the 1980s, Germany Had a "Two-And-A-Half" Party System Meaning

Until the 1980s, Germany had a "two-and-a-half" party system meaning that

A) it was dominated by two large parties and one small one.
B) although two parties dominated national politics, a variety of smaller ones dominated Länder politics.
C) two parties dominated national politics while a small third party dominated Länder politics.
D) governing coalitions were always comprised of two major parties with a third junior partner.
E) governing coalitions were necessary.