Answer:
Option B is correct.
 angle EDC and angle ADB 
Explanation:
Vertical angles states that they are a pair of non adjacent angles formed when two lines are intersects , also they never share a side and they always have a common vertex.
From the given figure.
Two lines which are intersecting i.e, AC and EB
Common vertex = D
then by definition of vertical angles:
 and
 and 
 are vertical angles.
 are vertical angles.
therefore, a pair of vertical angles in the figure is angle EDC and angle ADB