Question

1. which triangle is inscribed in a circle?

Explanation:

Step1: Recall definition of inscribed triangle

An inscribed triangle in a circle has all its vertices on the circle.

Step2: Examine each option

In option a, all three vertices of the triangle touch the circle. In option b, the circle is inside the triangle and vertices don't all touch the circle. In option c, the circle is inside the triangle and vertices don't all touch the circle. In option d, one vertex of the triangle does not touch the circle.

Answer:

a