Can someone i can’t figure it out i’m so confused

From the information given above, D is the answer which has a constant proportionality equal to 1.

“ a line segment that has the endpoints on the circle and passes through the midpoint is called the diameter. the diameter is twice the size of the radius. a line segment that has its endpoints on the circular border but does not pass through the midpoint is called a chord. a circle is the same as 360 small circle up the number 0 . i hope this .