While you fill out the form the selected answers are stored in Flash. When you click submit at the end of the survey the Flash movie generates XML in the form:
<Survey Status="1" NavPosition="">
<UserInfo Name="sberry2a"/>
<Questions>
<Q QId="1" TypeId="1" Answer="1"/>
<Q QId="2" TypeId="3" Answer="02/1979"/>
<Q QId="3" TypeId="3" Answer="67"/>
<Q QId="4" TypeId="4" Answer="180"/>
<Q QId="5" TypeId="1" Answer="2"/>
<Q QId="6" TypeId="1" Answer=""/>
<Q QId="7" TypeId="1" Answer=""/>
<Q QId="8" TypeId="3" Answer="3"/>
<Q QId="9" TypeId="3" Answer="2"/>
<Q QId="10" TypeId="3" Answer="3"/>
...
etc
...
</Questions>
</Survey>
This XML gets posted to http://www.vitaminid.com/webapp/wcs/stores/servlet/GetSurveyResult?storeId=201&flash=true which is most likely a Java servlet that parses the XML and based on the results makes recomendations.
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