Which of the following mortgage-backed securities is most likely to feature credit tranching?

Commercial mortgage-backed securities often feature credit tranching in which subordinated tranches are the first to absorb credit losses. Sequential-pay CMOs employ time tranching in which all principal payments flow to Tranche 1 up to its principal amount, then to Tranche 2 up to its principal amount, and so on. Agency RMBS are pass-through securities and do not feature credit tranching or time tranching.