A bean plant grows at a constant rate for a month. After \( 10 \) days, the plant is \( 25 \) centimeters tall. After \( 20 \) days, the plant is \( 45 \) centimeters tall. Which equation models the height of the plant, \( y \) , after \( x \) days?
A. \( y + 25 = 2 ( x + 10 ) \)
B. \( y - 25 = \frac { 1 } { 2 } ( x - 10 ) \)
C. \( y - 10 = \frac { 1 } { 2 } ( x - 25 ) \)
D. \( y - 25 = 2 ( x - 10 )\)