Answer:
Field Experiment
Step-by-step explanation:
According to my research on different types of experimentation methods, I can say that based on the information provided within the question this would be called a Field Experiment. This is a type of experiment that is done in the daily lives of the subjects and their environment, and the researcher has no control over the variables surrounding the experiment. This situation can be called a field experiment since the company is sending the emails to potential customers who will view it during their everyday life/routine and the company has no control over any other variables other than the email.
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