The best choice is the third option, changing the variables to determine how the drug affects children. By changing the variables, the scientist will be sure about the result he gets from the first trial.
EXPLANATION:
A scientist has completed several trials to see how a new drug affects adults. It means that he has known how a new drug affects adults. The result might be positive or negative. Furthermore, there is also a chance that the scientist gets various results from his several trials. His first trial might show a positive effect of the new drug to adults. On the other hand, the second result might show the negative result of the effect of a new drug to adults. Thus, his way of conducting several trials during his research the right step. The various results from his several trials will ensure the validity of his research.
Moreover, if the scientist wants to assess the validity of his experimental design and result, he might change the variables to determine how the drug affects children, although this step might be dangerous for the children as the subject of this research. Yet, changing the variables to determine the drug affects children will be the best way to assess his research validity, among all of the other options. By changing the variables, the scientist will get different results from his previous trials so that it will ensure that his data in his research is valid. Changing the variables can also become a comparison of his previous trials.
LEARN MORE:
If you’re interested in learning more about this topic, we recommend you to also take a look at the following questions:
1. Tyson is researching whether actors on prime-time television and hit movies negatively impact teenagers' body images. he is going undercover at a local high school to observe and participate with the students to better understand the world they live in. tyson is conducting which research method? brainly.com/question/4689529
2. Background research can be best completed through? brainly.com/question/6787567
KEYWORDS: research, subject of the research, changing the variables, changing variables in a reseacrh, variables, research variables, a scientist
Subject: English
Class: College
Sub-chapter: Research