Four cubes with edge lengths 1,2,3, and 4 are stacked as shown. What is the length of the portion of \overline{X Y} contained in the cube with edge length 3 ?

**Answer Choices**

A. \dfrac{3 \sqrt{33}}{5}

B. 2 \sqrt{3}

C. \dfrac{2 \sqrt{33}}{3}

D. 4

E. 3 \sqrt{2}