Understanding the Phrase "Power Behind the Throne"
The expression "parties are the power behind the throne" is often attributed to political theorists, particularly to the work of political scientist Finer. This phrase emphasizes the significant influence that political parties have on governance, even when they do not hold formal power.

Key Theoretical Perspectives
- **Finer's Contribution**:
- Finer argued that political parties play a crucial role in shaping policies and political outcomes. They may not always be in direct control, but their influence often guides decision-making processes.
- **Context of Political Parties**:
- Political parties organize individuals with similar interests and ideologies, creating a collective force that can sway political agendas and governmental actions.


Contrast with Other Thinkers
- **Grotius**:
- Focused on natural law and the moral basis of governance, rather than the dynamics of political parties.
- **Montesquieu**:
- Emphasized the separation of powers and the importance of checks and balances, but did not specifically address the influence of parties.
- **Rousseau**:
- Explored concepts of social contract and general will, placing less emphasis on the role of political parties in governance.

Conclusion
The assertion that "parties are the power behind the throne" highlights the essential role of political parties in shaping governance. Finer's perspective underscores that while parties may not always be visible in leadership roles, their influence is a significant driving force in political systems. Thus, the correct answer is indeed option 'D' - Finer.