Brazil Has a Weak Party System Because of All of the Following

Brazil has a weak party system because of all of the following EXCEPT

A) its historical circumstances, such as the corporatism of the New State era making the formation of independent political parties difficult.
B) the country's open list proportional representation system that creates incentives for politicians to ignore party labels because voters can easily cross party lines.
C) party loyalty is weak among both voters and politicians.
D) candidates could easily shift their party affiliation until 2007, even in the midst of an election.
E) corruption within Brazil's political parties has led to the citizenry to reject party labels and loyalty.