Answer:
Option C
Step-by-step explanation:
Given that Sarah's parents are concerned that the she seems short for her age.
From the data given we find regression equation connecting age and height is
[tex]y = 71.95 + 0.3883(x).[/tex]
Actual observation shows for 51 months her height was 91
Predicted height =
[tex]71.95 + 0.3883(51).\\=91.7533[/tex]
Actual height = 91
Residual = observed - actual
= -0.7533
=-0.75
Option C is right