When a peacock eats a snake,which eats insects,and insects feed on green plants,the peacock is a/an:

$A$: Successional process starts only in those areas where no living organisms ever existed.
$R$: These areas are not supported by physical environmental conditions.

The functional aspects of an ecosystem mainly include which of the following?

Identify the basic components of an ecosystem.

Assertion : In tropical rain forests,$O-$ horizon and $A-$ horizon of soil profile are shallow and nutrient-poor.
Reason : Excessive growth of micro-organisms in the soil depletes its organic content.

Match the following columns:

Column-$I$	Column-$II$
$P$. Herbivores	$I$. Directly dependent on plants
$Q$. Carnivores	$II$. Indirectly dependent on plants
$R$. Saprophytes (Fungi)	$III$. Dependent on dead or decaying matter