(4)For the purposes of this section "property held under trust" includes a business undertaking so held, and where a claim is made that the income of any such undertaking shall not be included in the total income of the persons in receipt thereof, the Assessing Officer shall have power to determine the income of such undertaking in accordance with the provisions of this Act relating to assessment; and where any income so determined is in excess of the income as shown in the accounts of the undertaking, such excess shall be deemed to be applied to purposes other than charitable or religious purposes.
