Data Sufficiency

I came up with Option B, as the longest chord is the diameter and can be compared.
Any other thoughts.

What is the source?

IMO: C

Question:
Area X > Area Y?
or
radius x > radius y?

1. The circumference of X>Z and the circumference of Z<Y.
means 2*pi*rx > 2*pi*rz, 2*pi*rz < 2*pi*ry --> No information about the relationship between rx and ry. So, Not sufficient.

2. The difference between the longest chords of Y and Z is more than the difference between the longest chords of x and y.
If diameter (Dz) = 2, Dy = 4, and Dx=3, then |Dz-Dy| = 2 and |Dz-Dx| = 1. In this case, y>x.
However, if Dz=3, Dy=2, Dx=5, then |Dz-Dy|=1 and |Dz-Dx|=2. In this case, x>y.
So, Stat 2 is not sufficient.

Combined together --> from stat 1 we know that rx>rz, and rz<ry. From stat 2, the difference between the longest chords of Y and Z is more than the difference between the longest chords of x and y (Case 1). Thus, sufficient.

OA?

yuliawati wrote:What is the source?

IMO: C

Question:
Area X > Area Y?
or
radius x > radius y?

1. The circumference of X>Z and the circumference of Z<Y.
means 2*pi*rx > 2*pi*rz, 2*pi*rz < 2*pi*ry --> No information about the relationship between rx and ry. So, Not sufficient.

2. The difference between the longest chords of Y and Z is more than the difference between the longest chords of x and y.
If diameter (Dz) = 2, Dy = 4, and Dx=3, then |Dz-Dy| = 2 and |Dz-Dx| = 1. In this case, y>x.
However, if Dz=3, Dy=2, Dx=5, then |Dz-Dy|=1 and |Dz-Dx|=2. In this case, x>y.
So, Stat 2 is not sufficient.

Combined together --> from stat 1 we know that rx>rz, and rz<ry. From stat 2, the difference between the longest chords of Y and Z is more than the difference between the longest chords of x and y (Case 1). Thus, sufficient.

OA?

OA:C
But

Dz=3, Dy=2, Dx=5, then |Dz-Dy|=1 and |Dz-Dx|=2. In this case, x>y.

in this case the condition The difference between the longest chords of Y and Z is more than the difference between the longest chords of x and z is not satisfied.

as per my interpretation: Y-Z>X-Z
so i thought its option B
Is any thing wrong in my interpretation??