21.—(1) The Secretary of State may require any person who has—
(a)applied for approval as a supplier under regulation 19; or
(b)claimed reimbursement of an amount in respect of milk, dried milk or vitamins supplied in accordance with these Regulations,
to furnish him, or an officer duly authorised in that behalf, with such information or evidence, whether in the form of documents or otherwise, as may be reasonably needed in connection with approving that person as a supplier or reimbursing that person.
(2) An officer to whom a person is required, under paragraph (1), to furnish information or evidence shall produce to that person, if required to do so, his authority from the Secretary of State.
(3) Where documents specified by the Secretary of State or an authorised officer under paragraph (1) are produced—
(a)he may take copies of them or extracts from them, and
(b)the person producing them, or where that person is a body corporate, any other person who is a present or past officer of, or is employed by, the body corporate shall provide an explanation of them if requested by the Secretary of State or an authorised officer.
(4) Where documents specified under paragraph (1) are not produced, the person who was required to produce them shall state, to the best of his knowledge and belief, where they are.