Find the Radius of Convergence of the Series $\sum _ { n = 0 } ^ { \infty } \left( \frac { x } { 6 } \right) ^ { n }$

Multiple Choice

Find the radius of convergence of the series $\sum _ { n = 0 } ^ { \infty } \left( \frac { x } { 6 } \right) ^ { n }$ .

A) 12
B) 14
C) 1
D) 7
E) 6