Sufficiency of activities for renewal of 80g

Dear Friends,

Please help me in this query.

Is 'sufficiency of activities' or 'sufficiency of utilization of income' of a charitable trust is necessary for renewal of approval under section 80G of the Act?? And what does mean about 'sufficiency of activities' or 'sufficiency of utilization of income' , is it defined anywhere, because I tried a lot but could not find any case law, or meaning or such condition for renewal of 80G. Please provide some guidance, and also refer some case law. please.

From 

Priyanka