Which of the following is characteristic of complex multicellularity?
a. All cells are exposed to an exterior surface.
b. The interior cells are exposed to a different physical and chemical environment than the exterior cells.
c. All cells express the same genes.
d. All cells are exposed to an interior surface.
e. All of the above are true.

The correct answer is option b. "The interior cells are exposed to a different physical and chemical environment than the exterior cells".

Explanation:

Complex multicellularity is a characteristic that large organisms comprised of thousands of cells posses. The organisms with complex multicellularity have their cells organized into different tissues in a three dimensional arrangement, that often involves the development of organs. One characteristic of complex multicellularity is that the interior cells are exposed to a different physical and chemical environment than the exterior cells. For instance, skin cells have adapted to serve as a barrier to pathogen and environmental conditions, while blood cells have adapted to transport nutrients and serve in the immune system.

a fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.[1] the age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years.[2] fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[3] other commonly used derivatives include kerosene and propane. fossil fuels range from volatile materials with low carbon to hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. methane can be found in hydrocarbon fields either alone, associated with oil, or in the form of methane clathrates.

the theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust over millions of years was first introduced by andreas libavius "in his 1597 alchemia [alchymia]" and later by mikhail lomonosov "as early as 1757 and certainly by 1763".[4] the first use of the term "fossil fuel" was by the german chemist caspar neumann, in english translation in 1759.[5]

in 2017 the world's primary energy sources consisted of petroleum (34%), coal (28%), natural gas (23%), amounting to an 85% share for fossil fuels in primary energy consumption in the world.[6] non-fossil sources in 2006 included nuclear (8.5%), hydroelectric (6.3%), and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%.[7] world energy consumption was growing at about 2.3% per year. in 2015 about 18% of worldwide consumption was from renewable sources.[8]