Question

Which one of the following is a true micro-ecosystem?
A
One litre of water from a pond kept in an air tight flask.
B
One litre of tap water in a flask covered over by cotton plug.
C
Ten litre of boiled pond water covered over by a lid.
D
One litre of pond water closed with a cork having gas exchange tube.
Hard
Solution

Verified by GMS
Correct option is D)