(a) Except as provided in subsection (b), no person eligible for dependency and indemnity compensation by reason of any death occurring after December 31, 1956, shall be eligible by reason of such death for any payments under (1) provisions of law administered by the Secretary providing for the payment of death compensation or death pension, or (2) subchapter I of chapter 81 of title 5.

(b) A surviving spouse who is eligible for dependency and indemnity compensation may elect to receive death pension instead of such compensation.