The main advantage of the parliamentary form of government is that

1. The parliamentary form of government is characterized by the fusion of the executive and legislature, unlike a presidential system where they work independently. Thus, (A) is incorrect. 2. While parliamentary systems can be responsive, they may lack continuity of policy if governments are unstable. Efficiency varies and is not an inherent guaranteed advantage over other systems. Thus, (B) is debatable and often considered incorrect as the primary advantage. 3. The defining feature and main advantage of the parliamentary system is the principle of collective responsibility, where the executive (Council of Ministers headed by the Prime Minister) remains responsible to the legislature (specifically the lower house in bicameral systems like India's Lok Sabha). The government holds office only as long as it commands the confidence of the legislature, ensuring accountability. Thus, (C) is correct. 4. The head of the government (Prime Minister) in a parliamentary system can be changed without a general election through internal party processes or if the ruling party/coalition loses the confidence of the legislature. Thus, (D) is incorrect.