Biogas generation is a three stage anaerobic digestion of animal and other organic wastes. Study the following flow chart and select the correct option for stages I, II and III.

Read the following statements and select the correct option.
Statement I: Biocontrol refers to the use of biological methods for controlling plant diseases and pests.
Statement II: Use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.

When a natural predator (living organism) is applied on the other pathogen organisms to control them, this process is called as

Fill up the blanks by selecting the correct option.
(i) Biogas is a mixture of gases which predominantly contains _____ and is used as _____.
(ii) Methanogens are commonly found in the _____ during sewage treatment.
(iii) ______ species are free-living fungi and effective biocontrol agents of several plant pathogens.