If the length of the longest chord of a certain circle is 22, what is the radius of that certain circle?
Choose the most appropriate option:
A) 11
B) 5
C) 10
D) 15
E) 20

Rationale: "longest chord of a circle is the diameter of the circle diameter = 2 * radius if diameter of the circle is given as 22 = 2 * 11 so radius of the circle = 11 correct answer - a"
Answer: A