During the liquidation (or payout) phase of an annuity, the annuitant receives periodic payments:

The annuitant (D) is the individual designated to receive the payments, as they are the insured party in the contract.

The owner (A) is often the annuitant but may differ; the owner controls the contract but does not necessarily receive payments.

The beneficiary (B) receives the death benefit if the annuitant passes away, not the periodic payments.

"Nominator" (C) is not relevant terminology in annuities.