Let's examine your answer choices: A The arc length of the smaller circle is half the arc length of the larger circle. Hmmmm that can't be right. The arc length of a 60° angle must be equal to the arc length of another 60° angle! Hey! Would you look at that! With that knowledge you can answer the question! The correct answer is B because the arc length of a 60° angle is equal to the arc length of another 60° angle! So the correct answer is B! Hope that helps!