\(\Rightarrow \) \(\begin{matrix}
O \\
|| \\
-C- \\
\end{matrix}\) group
Negative iodoform test \(\Rightarrow \) \(\begin{matrix}
\,\,\,\,\,\,\,\,\,O \\
\,\,\,\,\,\,\,\,\,|| \\
C{{H}_{3}}-C- \\
\end{matrix}\) group is absent
Negative Tollens' test \(\Rightarrow\) ketone
Hence, the compound is \(3 -\) pentanone.
\(\underset{\begin{smallmatrix}
3\,-\,Pen\tan one \\
({{C}_{5}}{{H}_{10}}O)
\end{smallmatrix}}{\mathop{\begin{matrix}
O \\
|| \\
C{{H}_{3}}C{{H}_{2}}-C-C{{H}_{2}}C{{H}_{3}} \\
\end{matrix}}}\) \(\xrightarrow{\operatorname{Re}duction}\) \(\underset{n\,-\,Pen\tan e}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}C{{H}_{3}}}}\)
$[Figure]$ $\xrightarrow[{(ii){H_2}O}]{{(i)\,{C_2}{H_5}MgBr}}A\xrightarrow{{HCl}}B$