Which pyramid is always upright, can never be inverted?

Which of the following pyramids is always upright and can never be inverted?

Which of the following pyramids is always upright and can never be inverted ?

Which pyramid is always upright ? Why?

Which of the following statement/s regarding ecological pyramid is/are wrong? I. In most ecosystem, all the pyramids, of number, of energy and biomass are upright. II. Each trophic level has a certain mass of living material at a particular time called as the standing crop. III. The pyramid of biomass in sea is generally upright because the biomass of fishes far lower that of phytoplankton. IV. Pyramid of energy is always upright, can never be inverted. V. Energy at a lower trophic level is always less than at a higher level.

Why is the pyramid of energy is always upright? Can it ever be inverted?

Justify the statement ,"Pyramid of energy is always straight and can never be inverted "

The pyramid of energy is always upright.