The line segment from A(1,2) to B(3,3) can be transformed to the line segment from A^{\prime}(3,1) to B^{\prime}(4,3), sending A to A^{\prime} and B to B^{\prime}, by a rotation centered at the point P(s, t). What is |s-t|?
Answer Choices
A. \dfrac{1}{4}
B. \dfrac{1}{2}
C. \dfrac{2}{3}
D. \dfrac{3}{4}
E. 1