The correct answer is: D. Kamrup
The Deputy Commissioner functions as the District and Sessions Judge in Kamrup district.
The Deputy Commissioner is the head of the district administration in India. He/She is appointed by the state government and is responsible for the overall administration of the district. The Deputy Commissioner is also the District Magistrate and the District Collector.
The District and Sessions Judge is a judicial officer who is responsible for the administration of justice in the district. He/She is appointed by the state government and is responsible for the trial of criminal cases and the disposal of civil suits.
In Kamrup district, the Deputy Commissioner functions as the District and Sessions Judge. This means that the Deputy Commissioner is responsible for both the administration of the district and the administration of justice.
The other options are incorrect because the Deputy Commissioner does not function as the District and Sessions Judge in those districts.
In Dhubri district, the District and Sessions Judge is a separate judicial officer who is appointed by the state government.
In Karbi-Anglong district, the District and Sessions Judge is a separate judicial officer who is appointed by the state government.
In Karimganj district, the District and Sessions Judge is a separate judicial officer who is appointed by the state government.