# The largest value of $r$ for which the region represented by the set $\{ \omega \in C | \omega - 4 - i | \leq r \}$ is contained in the region represented by the set $\{z \in C / |z-1| \leq |z+i| \}$, is equal to :
( A ) $\frac{3}{2}\sqrt{2}$
( B ) $\sqrt{17}$
( C ) $\frac{5}{2}\sqrt{2}$
( D ) $2\sqrt{2}$