Answer:
Option D
Explanation:
We have, $S_{n}=\frac{4^{n}-3^{n}}{3^{n}}$
For $n=1,S_{1}=t_{1}=\frac{4-3}{3}=\frac{1}{3}$
For $n=2,S_{2}=t_{1}+t_{2}=\frac{4^{2}-3^{2}}{3^{2}}=\frac{7}{9}$
$\therefore$ $t_{2}=\frac{7}{9}-t_{1}=\frac{7}{9}-\frac{1}{3}=\frac{7-3}{9}=\frac{4}{9}$