Answer:
The correct option is C. 30°
Step-by-step explanation:
Construction : Join OB and OA
Now, m∠ECB = 51°
Now, ∠ECB and ∠EOA are formed on the same base
⇒ m∠EOA = 2 × m∠ECB
⇒ m∠EOA = 2 × 51°
⇒ m∠EOA = 102°
Now, Angle in the arc = Angle formed by the arc at the center
⇒ m∠AOB = measure of arc AB
⇒ m∠AOB = 72°
Now, m∠EOA = 102° - 72°
⇒ m∠EOA = 30°
Since, Angle in the arc = Angle formed by the arc at the center
⇒ Measure of arc EA = measure of the angle EOA
⇒ Measure of arc EA = 30°
Therefore, The correct option is C. 30°
