What Effect Does 'Centering' Have on the Data in the Following

Multiple Choice

What effect does 'centering' have on the data in the following experiment In their study of 'Using individual growth model to analyse the change in quality of life from adolescence to adulthood' (2006) , Chen and Cohen conducted interviews on 3 different occasions over a period of time and the following graph demonstrates the physical health changes noted over these 3 periods in 20 of their sample.
Individual Physical Health Change (raw data, n = 20)
Chen and Cohen Health and Quality of Life Outcomes 2006 4:10 doi:10.1186/1477-7525-4-10

A) It makes the slope more visible.
B) It makes the intercept more interpretable.
C) It makes the variance more evident.
D) None of the above.