Which of the following statements about correlation and causation is true?

Select one:

a.

Correlation and causation can never be present in the same system.

b.

Correlation can lead to causation if the source of variation among two things is also a cause and effect relationship.

c.

The difference between correlation and causation is statistical significance.

d.

If the statistical significance is high enough, then correlation is representative of causation.

e.

Correlation and causation are both present in all things at all times.