Usually, why do you have a greater number of organisms at the lower trophic levels?

The energy available to the organism at the third trophic level is called

Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the

Organisms of a higher trophic level which feed on several types of organisms belonging to a number of lower trophic levels constitute the :

Assertion (A) : In a food chain members of successive higher levels are fewer in number. Reason (R ): Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.

[A] : In a food chain , membrane of successive higher levels are fewer in number . [R] : Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level .