Galton introduced the idea of correlation (or co-relation) and showed which of the following to be true?

A. A correlation of -1 indicates that there is no relationship between the two variables being considered.
B. Correlations should only be used with variables that are normally distributed.
C. If variable A (e.g. height) shows a correlation with variable B (e.g. weight) of +10, then we know that A caused
D. IQ was correlated with job performance.