Answer:
Option (C)
Step-by-step explanation:
The Carboniferous period is one of the important periods of the Paleozoic era, which started about 360 million years back and ended by about 300 million years back.
The Carboniferous period is characterized by the presence of swampy forests, where the dominant plants were the ferns, club mosses, some primitive conifers and other types of seedless plants.
These plants were abundantly present covering a large portion and comprised of vast quantities of organic matter, which were later buried and transformed into the Carboniferous coal.
Thus, the correct answer is option (C).