Q. Assertion (A) The pyramid of energy is always upright.
Reason (R) The flow of energy is unidirectional.

 546  169 Ecosystem Report Error

Solution:

Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
Pyramid of energy is always upright because the flow of energy is unidirectional. All of the energy stored by the autotrophs in the form of food is available to the herbivores and then carnivores food.