Since BCE is an inscribed angle, it measures half the measure of the inscribed arc.
Angle BCE inscribes the arc BE of 180°, we have:
[tex]\begin{gathered} \text{BCE}=\frac{BE}{2} \\ BCE=\frac{180}{2} \\ \text{BCE}=90\degree \end{gathered}[/tex]
Therefore the correct option is 1)
