Read this: A large portion of music played on this format are either considered oldies or recurrent. It often deals with modern romantic and sexual relationships (and sometimes other adult themes such as work, raising children, and family) in a thoughtful and complex way. Soft AC, which has never minded keeping songs in high rotation literally for years in some cases, does not appear necessarily to be facing similar pressures to expand its format. Soft AC includes a larger amount of older music, especially classic R&B, soul, and 1960s and 1970s music, than hot AC.

Along with classic R&B, what genre is notably featured on soft AC stations?
What is the answer? (If it cannot be answered, return "unanswerable")
soul