Chapter 14 - Sequences, Series, and the Binomial Theorem - 14.1 Sequences and Series - 14.1 Exercise Set - Page 894: 5

$\text{A}\text{. }3,9,27,81,.....$

${{3}^{n}}$ So, between $\text{A}\text{. }3,9,27,81,.....$ and $\text{B}\text{. }3+6+9+12+15$, description A represents the general term ${{3}^{n}}$. After all, we see that: $$ \frac{9}{3} = 3 $$ Thus, the general term ${{3}^{n}}$ from the provided description is $\text{A}\text{. }3,9,27,81,.....$.