this is a relative question, depending on popularity and localle any or all could be the correct choice.
DSL uses your phone line (uses filters on your phones)
Cable uses cable (no kidding, lol) and is approximatly the same as DSL otherwise
WIFI i do not have any experience with, atleast not long term, i'm not sure if it is appropriate in all homes.. or any, but it can be equal to both Cable and DSL as well.
There is no clear decision, the best thing to do would be to test each connection at friends/business etc, during peak times and see what kind of service you can expect