For purposes of clause (E) of paragraph (1)—

(A) An individual will be presumed, with respect to any month, to have been engaged in self-employment in such month until it is shown to the satisfaction of the Commissioner of Social Security that such individual rendered no substantial services in such month with respect to any trade or business the net income or loss of which is includible in computing (as provided in paragraph (5) of this subsection) his net earnings or net loss from self-employment for any taxable year. The Commissioner of Social Security shall by regulations prescribe the methods and criteria for determining whether or not an individual has rendered substantial services with respect to any trade or business.

(B) An individual will be presumed, with respect to any month, to have rendered services for wages (determined as provided in paragraph (5) of this subsection) of more than the applicable exempt amount as determined under paragraph (8) until it is shown to the satisfaction of the Commissioner of Social Security that such individual did not render such services in such month for more than such amount.