On $3^{rd}$ carbon atom two methyl substituent are attached.
So its name is $1$-chloro-$3,3$-dimethyl butane.

ક્રિયાશીલ કાર્બનની સંકરણ અવસ્થા માં ક્યો બદલાવ થાઈ છે ?
$\begin{matrix}
C{{H}_{3}}\,\,\,\,\,\,\, \\
|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
{{H}_{3}}C-C-CH=C{{H}_{2}} \\
|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
C{{H}_{3}}\,\,\,\,\,\,\,\,\, \\
\end{matrix}$

