The correct answer is: a) Cuttack
Cuttack is the district with the highest population density in Odisha. It is located in the central part of the state and has a population of over 3.5 million people. The district is home to a number of important historical and cultural sites, including the Cuttack Fort, the Jagannath Temple, and the Dhauli Stupa. Cuttack is also a major commercial and industrial center.
The other options are incorrect because they do not have the highest population density in Odisha. Khordha is the second most populous district in Odisha, with a population of over 2.5 million people. Sambalpur is the third most populous district in Odisha, with a population of over 2 million people. Ganjam is the fourth most populous district in Odisha, with a population of over 1.5 million people.
Cuttack has a population density of over 1,000 people per square kilometer. This is significantly higher than the population density of the other districts in Odisha. The high population density in Cuttack is due to a number of factors, including its location in the central part of the state, its historical and cultural importance, and its role as a commercial and industrial center.