Question

in which diagram are angles 1 and 2 vertical angles?

Explanation:

Vertical angles are formed when two lines intersect, and they are opposite each other, sharing only a common vertex (no common sides). The first diagram has two intersecting lines with angles 1 and 2 as opposite angles meeting at the vertex. The second diagram has angles sharing a common side and vertex, so they are adjacent angles, not vertical.

Answer:

A. The top diagram (with two intersecting lines, angles 1 and 2 opposite each other)