d
The optically inactive compound must containst achiral carbon atoms \((s)\). Option \((d)\) contains achiral carbon atom

\(\underset{2-chloropropanol}{\mathop{\begin{matrix}
   \,Cl\,  \\
   |\,\,  \\
   C{{H}_{3}}-C-CHO  \\
   |\,\,  \\
   H\,  \\
\end{matrix}}}\,\) \(\underset{2-chlorobu\tan e\,(chiral)}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Cl  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,  \\
   C{{H}_{3}}-C{{H}_{2}}-C-C{{H}_{3}}  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,H  \\
\end{matrix}}}\,\) 

\(\underset{(chiral)}{\mathop{\underset{2-chloropen\tan e}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Cl  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|  \\
   C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}-C-C{{H}_{3}}  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,H  \\
\end{matrix}}}\,}}\,\) \(\underset{(achiral)}{\mathop{\underset{2-chloro-2-methylbu\tan e}{\mathop{\begin{matrix}
   C{{H}_{3}}  \\
   |  \\
   C{{H}_{2}}-C-C{{H}_{3}}  \\
   |  \\
   Cl  \\
\end{matrix}}}\,}}\,\)