Terminate if all categories selected on a previous question was selected on the current question

I have 4 questions in a survey. An occupation question, province question, an age question and a category purchased question.
Occupation:
Do you work for...?

1. market research company


2. media group


3. advertising company


4. home improvement store


5. pharmacy store


6. liquor store


7. none of these

Province:

1. Alberta


2. Quebec


3. Ontario


4. None

Age:

1. Under 18


2. 18


3. 19


4. 20-34


5. and so on

Category purchased:

1. pharmacy


2. liquor


3. home improvement


4. none

How can I determine if a respondent works (occupation) in all categories that they selected in the 'category purchased' question so I can screen them out?