Answer:
B.

Step-by-step explanation:
We have been given an image of a circle and we are asked to find the measure of arc EH.
Since D is the center of circle and
, so the measure of arcs corresponding to these angles will be also equal.
We can see that angle EDG corresponds to arc EFG.



Since the measure of arc EFG equals to the measure of arc EH, therefore, the measure of arc EH is also 123 degrees and option B is the correct choice.