The correct answer is: a) Srikakulam.
Srikakulam is a coastal district in the Indian state of Andhra Pradesh. It is located in the northern part of the state, on the Bay of Bengal. The district is known for its mangoes and cashew nuts.
Mangoes are a popular fruit in India. They are a good source of vitamins A and C, and they are also a good source of fiber. Cashew nuts are a popular snack food. They are a good source of protein and minerals, such as magnesium and phosphorus.
The other options are incorrect because they are not coastal districts in Andhra Pradesh. Nellore is a district in the southern part of the state, Prakasam is a district in the central part of the state, and Guntur is a district in the western part of the state.