A researcher observes alcohol intake behavior during a party involving only students who were 21 years or older. To manage the observation period, every 10 min she observes behavior for 5 min, then takes 5 min off during the party. Which method was used to manage the observation period?

Time sampling

Explanation:

In an observation study, time sampling refers to a method of measuring behavior which is where an observer records activity at defined intervals. Therefore, it is a method of collecting  information in which a observer watch participants during research for a prescribed amount of time and record their particular behavior. As per the question, the researcher manage the observation period, every 10 min she observes behavior for 5 min, then takes 5 min off during the party and it an example of time sampling.

credit card number 4 is the right answer