Find the Nth Term of the Geometric Sequence $4,2,1 , \frac { 1 } { 2 } , \ldots$

Multiple Choice

Find the nth term of the geometric sequence.
- $4,2,1 , \frac { 1 } { 2 } , \ldots$

A) $a _ { n } = 4 \left( \frac { 1 } { 4 } \right) ^ { n - 1 }$
B) $a _ { n } = \frac { 1 } { 2 } ( 4 ) ^ { n - 1 }$
C) $a _ { n } = 4 \left( \frac { 1 } { 2 } \right) ^ { n - 1 }$
D) $a _ { n } = 4 \cdot 2 ^ { n - 1 }$