The angle bisector is the locus of points that are:

The angle bisector is a fundamental concept in geometry that refers to a line or ray that divides an angle into two equal parts. Its unique property is that any point located on the angle bisector has the same perpendicular distance to each of the two sides of the angle. This characteristic illustrates that the angle bisector is the locus of points that are equidistant from the two lines that form the angle.

In simpler terms, if you were to measure the shortest distance (perpendicular distance) from any point on the angle bisector to each side of the angle, those distances would be equal, confirming that the bisector functions effectively as a boundary that guarantees these equal distances. This is why the statement provided aligns perfectly with the definition and properties of an angle bisector.

The other options do not accurately describe the properties of an angle bisector:

• Being equidistant from two points describes the perpendicular bisector of a segment, not an angle bisector.
• The notion of being parallel to one line does not relate to the specific properties of angle bisectors.
• The idea of being concentric with a circle refers to circles that share the same center, which is entirely unrelated to angle bisectors.

This understanding reinforces the correct answer by