cash showing credit balance

mr a depoisit cash in the bank rs 20000/-

but dont show the source from where hi get this income

in this way he depoisit around cash of rs 750000/-  in year

but dont show from where hi get this income

result cash in the b/l showing credit balance 

my question is what he should do to show this cash as debit balance

option one increasing the sales or get the loan from other in cash

which is good and y

and allowable as per income tax