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. For a lot of people, drinking beer causes a desire for ice cream, or vice versa.
B. The correlation between "beer sales" and "ice cream sales" is negative.
C. A scatterplot of monthly ice cream sales vs. 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 above