In forest, a single tree can support a large of number of birds thus base showing producers in a pyramid of number will be narrower than the next slab showing primary consumers.

Correct Option: B

In forest, a single tree can support a large of number of birds thus base showing producers in a pyramid of number will be narrower than the next slab showing primary consumers.

A hydrosere is a plant succession which occurs in a freshwater lake. Second stage of hydrosere is submerged stage that is represented by Vallisneria, Hydrilla, Elodea, Utricularia etc.

Correct Option: D

A hydrosere is a plant succession which occurs in a freshwater lake. Second stage of hydrosere is submerged stage that is represented by Vallisneria, Hydrilla, Elodea, Utricularia etc.

Food web is a network of food chains or feeding relationships by which energy and nutrients are passed on from one species of living organisms to another.

Correct Option: D

Food web is a network of food chains or feeding relationships by which energy and nutrients are passed on from one species of living organisms to another.

A standing crop is the quantity or total weight or energy content of the organism, which are in a particular location at a particular time.

Correct Option: A

A standing crop is the quantity or total weight or energy content of the organism, which are in a particular location at a particular time.

An energy pyramid is the graphical representation of the tropic level (nutritionals) by which the incoming solar energy is transferred into an ecosystem. It can never be inverted in shape.

Correct Option: C

An energy pyramid is the graphical representation of the tropic level (nutritionals) by which the incoming solar energy is transferred into an ecosystem. It can never be inverted in shape.