Audit of a public welfare society & trust

If the trust/society is registered for income tax exemption then the audit is required because income is above 2.5 lac.

Dear Sir,

What's the meaning of Income here?

I mean is the total amount received is income   or   the surplus income left in the 'receipt & payments a/c' is income?

Pls clarify sir.

Thanks in advance.

It is the total amount received.