Curiously, during months when sales of beer are above average, sales of ice cream also tend to be above average; during months when sales of beer are below average, sales of ice cream also tend to be below average. Which of the following can we conclude from these facts?

A) The correlation between beer sales and ice cream sales is negative.
B) For a lot of people, drinking beer causes a desire for ice cream or vice versa.
C) A scatterplot of monthly ice cream sales versus monthly beer sales would show that a straight line describes the pattern in the plot, but it would have to be a horizontal line.
D) None of the answer options is correct.

The correct answer is letter "D": None of the answer options is correct.

Explanation:

The Correlation Coefficient (ρ) measures the degree of relationship between two variables. The value fluctuates between (-1) and (1). If the correlation is greater than (0) it is positive (direct correlation) while values lower than (0) imply the correlation is negative (inverse correlation). If the value equals (0), there is no correlation between the variables.

In the case, if during the months when sales of beer are above the average the sales of ice cream increase and if during the months when sales of beer are lower than average ice cream sales decrease, it implies there is a direct correlation between sales in beer and ice cream, thus, their correlation is positive.