Ecological pyramids can be based on the numbers of individual organisms at each level.

Tropic

Ecological pyramids can be defined as the energy pyramid in which there is a distribution of energy at each tropic level.

The highest energy lies at the base which constitutes of producers, that has the ability to absorb all the radiant energy from the sun to convert light energy into chemical energy.

Only 10 per cent energy is transferred from producers to the next tropic level. This is known as the 10 per cent law.

answer: b

coz red blood cells marrow and circulates the body for 120 days.