The first link in any food chain is always a green plant because
They are widely distributed
They are firmly fixed to the soil
They alone have a capacity to fix atmospheric $CO_2$ in the presence of sunlight
All of the above
The trophic level of Cuscuta, Orobanche and Albugo is
Whale is
The dominant second trophic level, in a lake ecosystem, is
The transfer or energy from organisms to organisms in a natural community establishes
Why are oceans least productive ?