Final answer:
A drop-off survey is a technique that is NOT a variation of a person-administered survey.
Step-by-step explanation:
A technique that is NOT a variation of a person-administered survey is the drop-off survey. In a drop-off survey, the respondent is provided with a survey questionnaire and asked to fill it out on their own without the presence of an interviewer. This method does not involve direct interaction with an interviewer, unlike in-home interviews, mall intercept interviews, telephone interviews, and in-office interviews.