Answer:
Option B: 26cm is the radius of smaller circle.
Explanation:
Given that:
Ratio of circumferences of two circles = 2:3
We know that circumference of circle is given by 2πr.
Radius of larger circle =
= 39 cm
Radius of smaller circle =

Now,

Putting radius of larger circle

Therefore,
The radius of smaller circle is 26cm.
Hence,
Option B: 26cm is the radius of smaller circle.