at the time any such quarters of coverage are earned—

(A) is described in subparagraph (B) or (D) of section 1101(a)(15) of title 8 ,

(B) is lawfully admitted temporarily to the United States for business (in the case of an individual described in such subparagraph (B)) or the performance as a crewman (in the case of an individual described in such subparagraph (D)), and

(C) the business engaged in or service as a crewman performed is within the scope of the terms of such individual’s admission to the United States.