Final answer:
The second law of thermodynamics in relation to a food web indicates that energy is transferred from higher to lower trophic levels with high entropy, meaning a loss of available energy at each level. The correct answer is option c.
Step-by-step explanation:
The second law of thermodynamics applied to a food web suggests that energy transfer within an ecosystem follows the principle that energy flows spontaneously from higher to lower trophic levels. This means that whenever energy is transferred from one trophic level to the next in an ecosystem, a large amount of that energy is lost, primarily as metabolic heat. The ecological efficiency or trophic level transfer efficiency (TLTE) quantifies how much energy is passed on, and it is found that generally only about 10 percent of the energy is transferred to the next level. The remaining 90 percent of the energy is used by the organisms for metabolic processes or given off to the environment as heat.
For example, in the Silver Springs ecosystem, only 14.8 percent of the energy was transferred from primary producers to primary consumers. This demonstrates the low efficiency of energy transfer between trophic levels, which in turn supports the second law of thermodynamics stating the tendency toward increased entropy or disorder when energy is transformed from one form to another. Therefore, the correct answer to the question is "c. Energy flows spontaneously from higher to lower trophic levels."