What is the diameter of a circle?

What is the diameter of a circle?

• A. The circumference of the circle.
• B. A line from the center to a point on the circle.
• C. The straight line distance from one point on the circle to another, passing through the center.
• D. The radius of the circle.

Answer: (C)

Diameter is the line segment that passes through the center and connects two points on the circle. This matches the description of a straight line distance from one point on the circle to another, with the center in between. It is the longest chord of the circle and equals twice the radius. The other statements describe the circumference (the distance around the circle) or the radius (a line from the center to the circle), not a line that spans across the circle through the center.

Diameter is the line segment that passes through the center and connects two points on the circle. This matches the description of a straight line distance from one point on the circle to another, with the center in between. It is the longest chord of the circle and equals twice the radius. The other statements describe the circumference (the distance around the circle) or the radius (a line from the center to the circle), not a line that spans across the circle through the center.