The variable that cannot be illustrated by a stem-and-leaf plot is C. Number of doctor visits during the past year.
What is a stem and leaf plot?
It can be inferred that a stem and leaf plot simply means the technique that is used to classify continuous or discrete variables.
In this case, the variable that cannot be illustrated by a stem-and-leaf plot is the number of doctor visits during the past year. This is because it's an ordinal variable.
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