Ralph arranges with the manager of a fantasy baseball league to observe and interview members as part of his research. At the baseball "draft," Ralph introduces himself to other members of the fantasy league and they agree to let him observe the draft and allow themselves to be interviewed, although they do not allow him to join the league (as his knowledge of other members' strategies may affect how he manages his fantasy team). His role as a field researcher is that of a ______.
a) note-taker
b) overt observer
c) participant observer
d) complete participant