Answer: Selection bias
Explanation:
Selection bias is defined as the process in which individual or group of individual are analyzed for selection process by lacking randomization property .This process displays that selected sample of individuals is not similar representative of major interest population.
According to the question,the systematic difference that occurs in selected group for experiment as per their last name is displaying that selected group does not represent interest population that is causing systematic error.Thus, this situation describes about selection biasing.
Answer: the answer is either b or c :)
Explanation: I hope this helped you out a little bit. <3
The <u>methods section</u> of any research article comprises an explanation of all the procedures that were used to conduct the experiment.
<h3>What is an experiment?</h3>
An experiment refers to an investigation which typically involves the process of manipulating an independent variable (the cause), in order to determine or measure the dependent variable (the effect).
As a general rule, the <u>methods section</u> of any research article should comprise an explanation of all the procedures that were used to conduct the experiment.
Read more on experiment here: brainly.com/question/27999103
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