I personally don't always like the combo box approach, in my instance, when the database was being designed, the coordinator of the survey had yet to make a decision on the wording to be used so the table was the best option.
If you have a very large survey, to me a table would be a better method because when the combo box values are used, they are stored as the entire text string, where as in a table approach they can store the string once and just a number for the records, which in a very large data set could affect the size. (IMHO)