18.48 Given quadrilateral $A B C D$, where $A D / / B C, \angle A=90^{\circ}, C D \perp$ $B D, D E \perp B C$, with the foot of the perpendicular at $E$, and $E$ is the midpoint of $B C$, then the incorrect statement among the following is
(A) $C D$ is the tangent to the circle passing through $A, B, D$.
(B) $B D$ is the tangent to the circle passing through $C, D, E$.
(C) $A D$ is the tangent to the circle passing through $B, D, C$.
(D) $C B$ is the tangent to the circle passing through $B, D, E$.
[Solution] According to the problem, we know that $\triangle B D C$ is an isosceles right triangle, so the circumcircle of $\triangle B D C$ has $E$ as its center and $B C$ as its diameter. Therefore, $(C)$ is true.
Similarly, we can prove that $(A)$ and $(B)$ are also true.
$\because B C$ is not perpendicular to $B D$,
$\therefore B C$ cannot be the tangent of the circumcircle of $\triangle B E D$.
Thus, the answer is $(D)$.