Answer:
B. 4π
Explanation:
The formula for the perimeter of a square is P = 4s, where s is the side length.
Given the square has a perimeter of 16 cm, then its side length (s) is:

Therefore, the side length of the square is 4 cm.
From observation of the given figure, the diameter (d) of the circle is equal to the side length of the square. Therefore, d = 4 cm.
The formula for the circumference of a circle is C = πd, where d is the diameter. Therefore, as the diameter of the circle is 4 cm, the circumference of the circle is:
