Final answer:
The main difference between CMBSs and RMBSs is that CMBSs are backed by commercial real estate loans, whereas RMBSs are secured by residential mortgages.
Step-by-step explanation:
The key distinction between commercial mortgage-backed securities (CMBSs) and residential mortgage-backed securities (RMBSs) is that CMBSs are most likely backed by commercial real estate loans.
This means that, unlike RMBSs that are backed by residential mortgages, CMBSs are secured by mortgages on commercial properties such as office buildings, retail spaces, hotels, and apartments. Both types of securities are tradable in the secondary market, and while the default risks can vary, they do not categorically determine the difference between CMBSs and RMBSs.