What is the measure of ABC?

Answer:
B
Step-by-step explanation:
the measure of the chord- chord angle ABC is half the sum of the arcs intercepted by the angle and its vertical angle , that is
∠ ABC = [tex]\frac{1}{2}[/tex] (AC + DE) = [tex]\frac{1}{2}[/tex] (75 + 45)° = [tex]\frac{1}{2}[/tex] × 120° = 60°