Answer: b. Remains of formerly living things buried by sediments in regions with little oxygen.
Explanation:
Fossil fuels are underground geological fueldeposits which are formed from the decaying of organic materials (animals and plants) over hundreds of millions of years in the earth's crust, which furthur processed into coal, crude oil, heavy oils or natural gas by exposure to pressure and heat
Fossil fules are present only in sedimentary rocks under litte oxygen the provide temperatures and pressures that do not kill fossil remains, unlike most igneousand metamorphic rocks.
The type of food chain that exists in a pond is called the grazing food chain. In a pond, the producers are phytoplankton like some algae and submerged plants found at the edges. The consumers have included zooplankton and the last decomposers are some bacteria, fungi, etc found at the bottom of the pond.
