An annuity that guarantees a given number of income payments, whether or not the annuitant is alive to receive them, is referred to as

This option accurately describes the annuity in question, as it guarantees a specified number of payments to the annuitant or their beneficiaries, irrespective of whether the annuitant is alive to receive them. This characteristic distinguishes it from other types of annuities that may depend on the annuitant's lifespan.

This term usually refers to annuities that provide benefits to a beneficiary after the annuitant's death, but it does not imply a guarantee of a fixed number of payments during the annuitant's life. Therefore, it does not accurately represent the characteristics of the annuity described in the question.

An irrevocable endowed annuity refers to a type of annuity that cannot be changed or canceled once established, but it does not guarantee a specific number of payments independent of the annuitant's survival. This definition diverges from the key feature of guaranteeing a fixed number of income payments.