ASSERTION (A): Soil microbiology is the study of microbes in soil, their functions and effects on soil properties. REASON (R): The microbial ecosystem of soil includes only biotic components of soil.

In the following question there are two statements, Assertion (A) and Reason (R), consider both the statements independently and mark your answers as under:
1. If A and R both are correct and R is correct explanation of A.
2. If A and R both are correct and R is not correct explanation of A.
3. If A is correct and R is incorrect.
4. If A is incorrect and R is correct.
5. If A and R both are incorrect.