Look back in your survey to figure out what field name(s) are for the questions (Click Web Site>Surveys and select your survey). They are found on the right side of the question.
Click People>Audiences. Click the "New Audience" button. Find the user field from your survey (found above) in the "Choose a User Field" dropdown. Then decide if you'd like to know anyone who answered (Has a Value) or people with a specific answer (dropdown in the last box). If you want to select multiple (but not all) answers, press control + answer to add responses.