District Level Officer (DLO) is the nodal officer at district level. answer is D as the question might be in relation to specific chapter or portion of study as Collector is DLO for particular district for administrative machinery of the government of state.

The nodal officer at the district level is the Collector. The Collector, also known as the District Magistrate, is a key administrative officer responsible for the overall governance and coordination of various departments and functions at the district level. Let's understand the roles and responsibilities of the Collector in detail:

1. Administrative Head:
- The Collector is the administrative head of the district and is responsible for maintaining law and order, ensuring the implementation of government policies, and delivering public services to the citizens.
- They supervise and coordinate the activities of various departments such as revenue, police, health, education, agriculture, etc.

2. Revenue Administration:
- The Collector oversees the revenue administration in the district. They are responsible for land records management, revenue collection, and settlement of land disputes.
- They also play a crucial role in implementing various land-related policies and schemes, such as land acquisition for infrastructure projects or distribution of land to landless farmers.

3. Disaster Management:
- The Collector is the nodal officer for disaster management in the district. They coordinate relief and rehabilitation efforts during natural disasters like floods, earthquakes, or cyclones.
- They work closely with other departments, NGOs, and the community to ensure effective disaster preparedness, response, and recovery.

4. Election Officer:
- The Collector serves as the District Election Officer (DEO) during elections. They are responsible for conducting free and fair elections in the district.
- They oversee the voter registration process, polling, counting of votes, and ensure compliance with election laws and regulations.

5. Magisterial Powers:
- As the District Magistrate, the Collector exercises magisterial powers. They can issue orders, prohibitory orders (Section 144), and take necessary action to maintain law and order in the district.
- They also handle cases related to public grievances, law violations, and administrative disputes.

6. Development and Welfare:
- The Collector plays a vital role in the development and welfare of the district. They monitor and evaluate government schemes and programs, ensuring effective implementation and utilization of resources.
- They work towards improving the socio-economic conditions of the district by promoting education, healthcare, sanitation, and other welfare initiatives.

In conclusion, the Collector is the nodal officer at the district level and performs a wide range of administrative, revenue, disaster management, election-related, and development responsibilities. They are the key point of contact for various government departments and act as a bridge between the government and the people at the grassroots level.