The correct answer is option 'C': original jurisdiction.

The Supreme Court of India is the highest judicial body in the country and has the power to decide disputes between the Centre (the central government) and the States (the state governments). This power is exercised under its original jurisdiction.

Original jurisdiction refers to the power of a court to hear and decide a case in the first instance, without it being appealed from a lower court. In the case of disputes between the Centre and the States, the Supreme Court has exclusive original jurisdiction, meaning that only the Supreme Court can hear and decide such cases.

Here is a detailed explanation of the power of the Supreme Court of India under its original jurisdiction:

1. Exclusive Jurisdiction: The Supreme Court has exclusive original jurisdiction in disputes between the Centre and the States. This means that no other court in India can hear and decide such cases.

2. Federal Structure: The power of the Supreme Court to resolve disputes between the Centre and the States is an essential feature of India's federal structure. It helps in maintaining the balance of power between the central government and the state governments.

3. Interpretation of the Constitution: The Supreme Court's power to decide Centre-State disputes also involves interpreting the provisions of the Constitution. The Court has the authority to interpret and determine the scope and extent of the powers of the Centre and the States as provided in the Constitution. This helps in clarifying any ambiguity or conflict in the constitutional provisions.

4. Judicial Review: Under its original jurisdiction, the Supreme Court can review the constitutionality of laws and actions of both the Centre and the States. It can strike down any law or action that is found to be unconstitutional. This power of judicial review ensures that the actions of the Centre and the States are in conformity with the Constitution and protects the fundamental rights of citizens.

5. Dispute Resolution: The Supreme Court's original jurisdiction also extends to resolving disputes between the Centre and the States regarding the distribution of powers, legislative competence, and administrative matters. It acts as an arbiter in such disputes and ensures that the interests of both the Centre and the States are protected.

In conclusion, the power of the Supreme Court of India to decide disputes between the Centre and the States falls under its original jurisdiction. This power is exclusive and plays a crucial role in maintaining the federal structure of the country, interpreting the Constitution, ensuring judicial review, and resolving disputes in a fair and impartial manner.