The correct answer is a) Thiruvananthapuram.
Lignite is a type of coal that is less mature than bituminous coal and anthracite. It is brown in color and has a high moisture content. Lignite is found in sedimentary rocks and is formed from the remains of plants that have been buried and subjected to heat and pressure over millions of years.
Lignite is used as a fuel for power plants and for the production of chemicals. It is also used in the manufacture of bricks, tiles, and other building materials.
Lignite deposits have been discovered in certain areas of Thiruvananthapuram, Kerala, India. The deposits are located in the Neyyar and Karamana river valleys. The lignite is of low quality and is not suitable for use as a fuel. However, it is being used to produce chemicals and building materials.
The other options are incorrect because lignite deposits have not been discovered in those areas.
a) Thiruvananthapuram: Lignite deposits have been discovered in certain areas of Thiruvananthapuram, Kerala, India. The deposits are located in the Neyyar and Karamana river valleys. The lignite is of low quality and is not suitable for use as a fuel. However, it is being used to produce chemicals and building materials.
b) Alappuzha: Lignite deposits have not been discovered in Alappuzha.
c) Kannur: Lignite deposits have not been discovered in Kannur.
d) Kozhikode: Lignite deposits have not been discovered in Kozhikode.