Using a compass and a straightedge, a student constructed a triangle in which overline XY is one of the sides.

•----------------------------------------------•
X Y

The compass is opened to a set length and two intersecting arcs are drawn above overline XY using X and Y as centers. The intersection of the two arcs is labeled as point Z.

What could not be the length of the compass so that â–łXYZ is isosceles?
A. greater than XY
B. less than 1/2 XY
C. equal to XY
D. greater than 1/2 XY