Answer:
Option (C)
Explanation:
Measure of the arc BC of a circle A = 60°
Since, measure of an arc is equal to the measure of the central angle that intercepts the arc.
Therefore, m∠A = 60°
Since, measure of the inscribed angle is half of the central angle subtended by the same arc.
Therefore, m∠A =
60° = 2 × m(∠BDC)
m∠BDC = 30°
Therefore, Option (C) will be the answer.