Which statement is true of carbohydrates
a carbohydrates form biological catalysts known as enzymes.
b carbohydrates carry the genetic information in plants.
c carbohydrates are major components of cell membranes.
d carbohydrates are a source of energy.

The correct answer is D carbohydrates are a source of energy .

Explanation:

Carbohydrates can be defined as Polyhydroxy Aldehydes or Polyhydroxy ketones.Carbohydrates are major source of energy in our body.

                   Carbohydrate such as glucose is broken down to through glycolysis, TCA cycle and oxidative phosphorylation collectively called aerobic respiration to generate carbon di oxide,H2O and adenosine Tri Phosphate or ATP.

            1 molecule of ATP is broken down to generate -30.5 kj/mole energy which is used as free energy by the cell to carry out various cellular and physiological process such as gluconeogenesis,Muscle contraction etc.

every el niño cycle is different. every year.

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]