The well known scientist Albert Einstein is the answer.
The researchers were most concerned about External events.
<h3><u>Explanation: </u></h3>
Quasi-experimental designs are different from true experimental designs. They resemble the experimental research but it is not the real one. There are various types of quasi-experiment design, one of the important designs is the pretest and posttest design which is discussed in the above scenario.
The most likely reason for the experimental effect is based on selection bias. Self-fulfilling Prophecy & Instrument Decay might be the potential cause of the internal validity that is linked with the experiment done by the staff.
The correct answer is the actor-observer bias.
The actor-observer bias (AOB) refers to the phenomenon where we attribute our own behavior to external factors beyond our personal control, while attributing others' behavior to factors internal to them, and fully within their control. In this instance, Tom believes that he is unable to stop gambling due to the negative influence of his friends (an external factor beyond his control), while believing that Barnaby is unable to stop gambling because he is addicted to it (a factor internal to Barnaby). Thus, Tom is demonstrating the actor-observer bias
