D) less socially stratified
16+5 =21. M is 16 if you do 21-5=16
Explanation:
Contamination can have undesirable consequences in real experiments, some of them are related to the feelings that may arise in the research participants, the contamination bias reduces the differences between the research groups, and can cause a comparison between the treatments of each different group, the which can generate conflicts and rivalries on the part of groups that consider themselves to be inferior to others. These contamination-related problems can significantly interfere with the research results.
Based on the information given this nonverbal communication is related to Identity management.
Identity management occur when a person tries to manage their identity in a social circle by using a strategy or technique.
A person can tend to use different identity management in order to cope when they are in the midst of people or group of people, such person may tend to smile often so as to make a great first impression about them self to others.
Using identity management may help to build confidence.
Inconclusion this nonverbal communication is related to Identity management.
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