select the correct answer from each drop - do...
select the correct answer from each drop - down menu. a dentist conducts a survey to determine whether a certain brand of mouthwash improves gum health more than others. when his patients come in for their regular cleanings, the dentist surveys them about their mouthwash use and makes a conclusion based on the survey results. the conclusion drawn from the study is because the sample is. in this instance, an study was conducted.
Answer
# Brief Explanations:
The dentist surveyed only his own patients during regular clean - ings. This sample is likely biased as these patients may have different oral health behaviors and needs compared to the general population. So, the conclusion is not valid. Also, this is an observational study as the dentist is just observing and collecting data on mouthwash use without manipulating any variables.
# Answer:
The conclusion drawn from the study is not valid because the sample is biased. In this instance, an observational study was conducted.