Stanley Plog managed to identify the different travellers based on a scale from allocentric/venture to psychocentric/dependable. Even though he is not a tenured researchers and mostly worked on private sectors, the research which he published on his books is considered to be revolutionary by other researchers.
I think the correct answer from the choices listed above is the second option. The researcher who identified three types of travelers on a continuum was Stanley Plog. Hope this answers the question. Have a nice day. Feel free to ask more questions.
