The correct answer among all of the given choices would be the third choice, CLOUDS.
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During the transfer of energy from one tropic level to the next tropic level around 90% of the total energy is lost in the metabolic processes in the form of heat. Hence only about 10% of the total energy can only be transferred from one tropic level to the next tropic level.
Answer:
From The School of Biomedical Sciences Wiki. Complementary base pairing is the phenomenon where in DNA guanine always hydrogen bonds to cytosine and adenine always binds to thymine. The bond between guanine and cytosine shares three hydrogen bonds compared to the A-T bond which always shares two hydrogen bonds.