Squares A B C D, E F G H, and G H I J are equal in area. Points C and D are the midpoints of sides I H and H E, respectively. What is the ratio of the area of the shaded pentagon A J I C B to the sum of the areas of the three squares?
Answer Choices
A. \dfrac{1}{4}
B. \dfrac{7}{24}
C. \dfrac{1}{3}
D. \dfrac{3}{8}
E. \dfrac{5}{12}