Answer:
Option: A is the correct answer.
The measure of ∠ABC is 60°.
Explanation:
From the intersecting chord theorem we have:
m∠ABC is the mean of the sum of the length of arc AC and length of arc DE.
Also it could be understood from the figure attached to the answer.
Hence, we have:
m∠ABC=(measure arc AC+measure arc DE)/2
⇒ m∠ABC=(45°+75°)/2
⇒ m∠ABC=120°/2
⇒ m∠ABC=60°
Hence, the measure of ∠ABC is:
60°