Find an Explicit Rule for the Nth Term of the Sequence

Multiple Choice

Find an explicit rule for the nth term of the sequence.
-The second and fifth terms of a geometric sequence are 9 and 243 , respectively.

A) $a _ { n } = 3 \cdot 3 ^ { n + 3 }$
B) $a _ { n } = 3 \cdot 3 ^ { n - 2 }$
C) $a _ { n } = 3 \cdot 3 ^ { n - 1 }$
D) $a _ { n } = 3 \cdot 3 ^ { n + 1 }$