Final answer:
Cindy is referred to as a participant-observer, which is a research method where the researcher immerses in a group to observe from an insider perspective.
Step-by-step explanation:
Cindy, who is an ethnographer trying to understand how mothers take care of toddlers, has joined a mother's group to collect data from her observations. She is engaging in participant observation, a research method where the researcher immerses herself in a group or social setting to make observations from an insider perspective. As she is both observing and participating in the culture of the mother's group, Cindy can be referred to as a b. participant-observer.