When bcbs payers for the primary and secondary policies are different, submit a cms-1500 claim to the primary payer, and after the primary payer processes the claim, generate a second cms-1500 claim to send to the secondary payer and include a copy of the primary payer's __________.

a. explanation of benefits
b. ub-04 or cms-1450
c. remittance advice
d. cms-1500 processed claim