Which of the Following Statements Are True?
A) When the Relationship

Which of the following statements are true?

A) When the relationship between x and y is positive, $S _ { x,y } = \sum _ { l = 1 } ^ { n } \left( x _ { l } - \bar { x } \right) \left( y _ { l } - \bar { y } \right)$
Will be positive, a negative relationship implies that $S _ { x y }$
Will be negative.
B) By changing the units of measurement of either x or y, $S _ { xy } = \sum _ { i = 1 } ^ { n } \left( x _ { i } - \bar { x } \right) \left( y _ { i } - \bar { y } \right)$
, can be made either arbitrarily large in magnitude or arbitrarily close to zero.
C) A reasonable condition to impose on any measure of how strongly x and y are related is that the calculated measure should not depend on the particular units used to measure them. This condition is achieved by using the sample correlation coefficient r.
D) All of the above statements are true.
E) None of the above statements are true.