Task: Question Answering
Input (English): Passage: Goodluck Jonathan served as Nigeria's president till 16 April 2011, when a new presidential election in Nigeria was conducted. Jonathan of the PDP was declared the winner on 19 April 2011, having won the election with a total of 22,495,187 of the 39,469,484 votes cast, to stand ahead of Muhammadu Buhari from the main opposition party, the Congress for Progressive Change (CPC), which won 12,214,853 of the total votes cast. The international media reported the elections as having run smoothly with relatively little violence or voter fraud, in contrast to previous elections. Question: What was the main opposition political party in 2011?
Output (English): Congress for Progressive Change