Three one-inch squares are placed with their bases on a line. The center square is lifted out and rotated 45^{\circ}, as shown. Then it is centered and lowered into its original location until it touches both of the adjoining squares. How many inches is the point B from the line on which the bases of the original squares were placed?
Answer Choices
A. 1
B. \sqrt{2}
C. \dfrac{3}{2}
D. \sqrt{2}+\dfrac{1}{2}
E. 2