A pediatrician records the age (in months) and the height (in inches) of a baby over time and creates a scatter plot. Using the scatter plot, the pediatrician determines that the model that can be used to predict the baby's height is y=1.3x+18, where y is the height of the baby and x is the age of the baby. What does the 18 in the equation tell us? Need help plz i will make you the brilliants

A
The baby grows 1.8 inches per year.

B
The baby weighs 18 pounds when born.

C
The baby was 18 inches when born.

D
The baby grows 18 inches per year.