Question

the height and arm span of a sample of 50 teenagers

identify the explanatory variable and the response variable for this relationship, if possible.

the explanatory variable, arm span of teenagers, helps explain the response variable, height of teenagers.

the explanatory variable, teenagers, helps explain the response variable, armspan of teenagers.

the explanatory variable, height of teenagers, helps explain the response variable, armspan of teenagers.

either variable, height or arm span, could be the explanatory variable, because each could be used to predict or explain the other.

Explanation:

An explanatory variable is used to predict or explain changes in the response variable. In the context of height and arm - span of teenagers, there is a mutual relationship. Height can be used to predict arm - span and vice - versa. For example, in a general population, taller people tend to have longer arm - spans and people with longer arm - spans tend to be taller. So, neither variable has a clear - cut role of only being an explainer or only being explained.

Answer:

Either variable, height or arm span, could be the explanatory variable, because each could be used to predict or explain the other.