The provisions of this subsection shall be applicable only in the case of an individual—

(A) with respect to whom at least one of the quarters elapsing prior to 1951 is a quarter of coverage;

(B) who attained age 22 after 1950 and with respect to whom less than six of the quarters elapsing after 1950 are quarters of coverage, or who attained such age before 1951; and

(C) (i) who becomes entitled to benefits under section 402(a) or 423 of this title or who dies, or (ii) whose primary insurance amount is required to be recomputed under paragraph (2), (6), or (7) of subsection (f) or under section 431 of this title .