Biased because the survey was conducted in a limited field of people aka health club which does not include other people, perhaps an unhealthy club? Or the people who are not a part of the health club? Or people who do not care about their health?
A biased question is a question where you cannot expect a fair reply from the respondents. The people reply in a specific way and its mostly inclined towards one aspect or one direction of the survey.
Now the question is : A beverage company conducts a survey in the lobby of a health club to determine people's favorite beverage.
This question is definitely biased as first its conducted in a lobby where there will be few people and mostly they will be employees of the health club. They all an answer the same way.
Secondly, the survey is conducted in a health club and people who visit such clubs usually do not prefer sodas or beverages.
Rather this survey would have conducted with few hundred people from both groups - the healthy preference and non healthy preference. Then it would have been a fair survey.
