Respuesta :
Answer:
C. Plane
Step-by-step explanation:
One definition of a circle is: "It is the set of all points in a plane that are at a given distance from a fixed point."
The undefined term is the word "plane."
You could define a plane as a flat surface with zero thickness and extends infinitely in all directions, but it isn't in the definition of a circle.
Euclid defined a plane as "a surface that lies evenly with the lines on it" before he defined a circle, so the meaning was understood.
A, B, and D are wrong. They aren't mentioned in the definition.
The blank space should be filled with; Choice C; Plane.
Definition of a circle
Among the definitions of a circle is: that a circle is the set of all points in a plane which are at a given distance from a fixed point, termed the center of the circle.
On this note, it follows that the undefined term is "plane."
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