The correct answer is (d) Jamnagar.
Ilmenite is a titanium-rich mineral that is found in beach sands and other sedimentary rocks. It is the most important source of titanium, which is used in a variety of industrial applications, including the production of steel, paint, and ceramics.
The Jamnagar district in Gujarat is one of the major producers of ilmenite in India. The ilmenite deposits in Jamnagar are located in the coastal areas of the district, and they are mined by open-pit methods. The ilmenite is then processed to extract the titanium, which is used in a variety of industrial applications.
The other options are incorrect because they are not coastal districts in Gujarat. Valsad is a district in the Dang Division of Gujarat, India. Bhavnagar is a district in the Saurashtra region of Gujarat, India. Surat is a city and a municipality in the Surat district in the Indian state of Gujarat.