○=> Correct option :
Diameter of circle P is the same length as the radius of circle Q.
○=> Steps to derive correct option :
Given :
Diameter of circle P = 26 cm
Radius of circle P :



Thus, radius of circle P = 13 cm
Diameter of circle Q = 52 cm
Radius of circle Q :



Thus, radius of circle Q = 26 cm
Radius of circle R = 52 cm
Diameter of circle R :



Thus, the diameter of circle R = 104 cm
☆ Conclusion :
▪︎Diameter of circle P is the same length as the radius of circle Q.
Therefore, the correct option is (C) Diameter of circle P is the same length as the radius of circle Q.