Assertion and ReasonAssertion (A): Energy flow in an ecosystem is unidirectional

Assertion and ReasonAssertion (A): Energy flow in an ecosystem is unidirectional

Assertion and ReasonAssertion (A): Energy flow in an ecosystem is unidirectional.
Reason (R): Energy captured by autotrophs does not revert back to solar input and is eventually lost as heat.
a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true, but Reason (R) is false.
d) Assertion (A) is false, but Reason (R) is true.