Ecosystem is a self-regulatory and self-sustained structural and functional unit of nature where biotic and abiotic components are linked together with the following processes :
(a) Productivity
(b) Decomposition
(c) Nutrient cycling
(d) Energy flow
Which of the statements given above is/are correct?
1
Only (a)
2
Only (a) and (b)
3
(a), (b), (c) and (d)
4
(a), (b) and (d)