To answer this question, you need to understand the different types of coal and their characteristics in terms of pollution. Let's go through each option to understand why it is correct or incorrect:
Option A) Lignite - This option is incorrect because lignite is known to release a great deal of pollutants into the air, making it more polluting.
Option B) Bituminous - This option is incorrect because bituminous coal also releases a great deal of pollutants into the air, making it more polluting.
Option C) Anthracite - This option is correct because anthracite coal releases less smoke and is considered to be less polluting compared to lignite and bituminous coal. It is known for its high carbon content and low sulfur content, which contributes to its lower emissions.
Option D) None of the above - This option is incorrect because the correct answer is indeed one of the given options.
The correct answer is C) Anthracite. This option is correct because anthracite coal releases less smoke and is considered to be less polluting compared to the other two types of coal.