High temperature: The organic material is compressed between Earth’s mantle, with very high temperatures, and millions of tons of rock and sediment above.
Absence of air: Oxygen is completely absent in these conditions, and the organic matter begins to transform into a waxy substance named kerogen.
High pressure: With more heat, time, and pressure, the kerogen undergoes a process called catagenesis, and transforms into hydrocarbons. In this way, Petroleum is formed.
Hence, option D is correct.