Passage Summary: If a country has only a few political parties, those parties have to deal with so many different topics that they are forced to compromise, making the government more productive.

Conclusion: Multiparty democracies with the fewest parties will have the most productive legislatures.

Reasoning: Fewer parties mean each party must take stands on more issues, which forces them to prioritize and increases their willingness to compromise.

Analysis: The argument relies on a logical chain: fewer parties leads to more issues, which leads to prioritization, which leads to compromise. However, the final jump to 'productivity' is unsupported. The argument assumes that a tendency to compromise is what actually makes a legislature productive. To find the necessary assumption, look for the missing link that connects the act of compromising to the result of being productive.