The Drombeg stone circle is a collection of megaliths (large prehistoric stones) located in Glandore, Ireland, that was used between 1100 BCE and 800 BCE.
The Drombeg stone circle measures approximately `31` ft across. Which of the following would be a reasonable approximation of its circumference?
A: 15.5
B: 49
C: 90
D: 97
E: 31π