A study of child development asks whether the age X (in months) at which a child begins to talk helps predict the child's score Y on anability test given several years later.The regression line of test score y on age x isY = - 1.5X +112.

According to this regression line, what happens (on average) each month a child delays speech?

The test score goes down 112 points.

The test score goes up 112 points.

The test score goes down 1.5 points.

The test score is 110.5.

The test score goes up 1.5 points.