Final answer:
Hugo should investigate the cause of the outlier at point (12, 2) and, unless it is due to an experimental error or unrelated factor, include it in his data, as it contributes valuable information to the relationship between sunlight exposure and plant height.
Step-by-step explanation:
When Hugo observes an outlier at point (12, 2), which indicates a plant that is unexpectedly short in height despite extended exposure to sunlight, it is important to consider why the outlier exists before deciding what to do with it. There might be several reasons for a plant to be an outlier, such as differences in individual plant health, soil conditions, error in measurement, or other uncontrolled variables. It is essential for the integrity of scientific research to include all data unless there is a valid reason to believe that the outlier is due to an error in the experiment or an extraneous factor not related to the variables being tested.
The most appropriate action for Hugo would be to first investigate the cause of the outlier. If he concludes that the outlier is due to an experimental error or a factor not relevant to his hypothesis on the effects of sunlight on plant growth, he could consider removing it. However, if the outlier is a legitimate result within the experimental conditions, it should be included, as it contributes to the understanding of the relationship between sunlight and plant growth. Therefore, the correct answer would be 'd) Hugo should include the outlier because it shows there is a relationship between hours of sunlight and plant height.'