Identify the correct sequence of coal grade formation from sedimentary to metamorphic rock:
(A) Peat (B) Anthracite (C) Bituminous (D) Lignite
Choose the correct answer from the options given below:

Correct option is C

Explanation:
Coal forms through the geological process of coalification, starting from plant material under heat and pressure over millions of years. The stages (from lowest to highest rank) are:
1. (A) Peat – Soft, partially decomposed plant material; low carbon, high moisture
2. (D) Lignite – Brown coal; low grade, higher carbon than peat
3. (C) Bituminous – Black coal; widely used in power plants and industries
4. (B) Anthracite – Hardest and highest grade, metamorphic in nature, with highest carbon content and calorific value
Additional Information:
· Peat and lignite are sedimentary in origin.
· Anthracite is a result of metamorphism under high pressure and temperature.
· This sequence reflects coal rank and energy content progression.