John Finds the Pearson R Correlation Coefficient Between Variable a and Variable

Multiple Choice

John finds the Pearson r correlation coefficient between variable A and variable B to be 0.00.Before concluding there is no relationship between the variables,John should

A) use a different set of participants.
B) restrict the range from which he samples.
C) construct a scatterplot of the data.
D) calculate the effect size for the relationship.