Since it involves all values in the data-set, the measure most affected by outliers is given by:
A. the mean
The mean of a data-set is given by the sum of all observations in the data-set divided by the number of observations.
The median is the 50th percentile, while the mode is the value that appears the most often in the data-set, that is, they do not involve outliers, only the mean does, hence option A is correct.
More can be learned about the mean of a data-set at https://brainly.com/question/24628525
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