Can you please post option too
Answer: b. Remains of formerly living things buried by sediments in regions with little oxygen.
Explanation:
Fossil fuels are underground geological fuel deposits 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.
Hence, the correct option is b.
Polyploidy is the term that describes the chromosomal abnormality of having extra chromosomes.
The flower mechanism that would not help them preventing pollination by a specie such as a foreign plant would be that the flowers of different species are then the same color and would attract the same pollinators.Hope this would be of help.