Question

Circle D is shown. Line segment F E goes through point D. Line segment C D is shown. Line segment G H goes from one side of the circle to the other side. Line segment A B is outside of the circle and intersects the circle at point B.
In circle D, which is tangent to the circle?

Line G H
Line segment A B
CD
EF

Answer 1

Line segment AB.

Reason: A tangent touches a circle at exactly one point. AB is outside the circle and meets it only at B. GH crosses the circle (two points), EF passes through the center (a secant/diameter), and CD is a radius — none of those are tangents.