63. Given that $a, b$ are the x-coordinates of the points where the parabola $y=(x-c)(x-c-d)-2$ intersects the x-axis, $a<b$, then $|a-c|+|c-b|=$ ( ).
A. $a-b$
B. $a+b-2 c$
C. $2 c-a-b$
D. $b-a$
Answer: D