Ans: B
Note that the first term is $4$ and the common difference is $3$. Therefore,
Note that the first term is $4$ and the common difference is $3$. Therefore,
$\begin{array}{rcl}
T(n) & = & 4 +3(n-1) \\
& = & 3n+1
\end{array}$
Therefore, the number of dots in the $8$th pattern
$\begin{array}{cl}
= & T(8) \\
= & 3(8)+1 \\
= & 25
\end{array}$
