Let's go through each part of the problem, based on the diagram provided:

(a) Center of the Circle

The center of a circle is typically the point where all the radii meet. In the given diagram, the point labeled O appears to be located at the center of the circle.

Answer: A. O

(b) Radii

Radii are the line segments that connect the center of the circle to any point on the circumference. In this diagram, the radii would be:

• $OA$
• $OB$
• $OC$
• $OD$

(c) Diameters

A diameter is a chord that passes through the center of the circle. In this case, the diameter would be the segment that connects two points on the circumference and passes through point $O$.

• $AC$ is the diameter.

(d) Chords

A chord is a line segment with both endpoints on the circle. In this diagram, the chords are:

• $AB$
• $AC$
• $AD$
• $BD$

(e) Secants

A secant is a line that intersects the circle at two points. In this diagram, the secants are:

• Line $EB$
• Line $BC$

(f) Tangents

A tangent is a line that touches the circle at exactly one point. In this diagram, the tangent appears to be:

• Line $AE$, as it only touches the circle at point $A$.

Would you like more details or have any specific questions?

Here are 5 relative questions based on this:

1. How do you differentiate between a secant and a tangent?
2. Can a chord ever be longer than a diameter?
3. How are the radii related to the diameter?
4. Why is point $O$ considered the center of the circle?
5. What would happen if a line passes through $O$ but doesn’t end at the circle?

Tip: The radius of a circle is always half the length of its diameter.