When acetaldehyde reacts with $PCl_{5}$,the resulting compound is

Identify the correct reagents for the given reaction sequence:

Match the List-$I$ with List-$II$.

List-$I$ (Reagents)	List-$II$ (Reaction Name)
$A$. $NH_2-NH_2, KOH$	$I$. Tollen's Test
$B$. $[Ag(NH_3)_2]OH$	$II$. Clemmensen Reduction
$C$. Aq. $CuSO_4$, Sodium Potassium tartarate, $KOH$	$III$. Wolff-Kishner Reduction
$D$. $Zn-Hg, HCl$	$IV$. Fehling's Test

Choose the correct answer from the options given below:

What is the correct order of reactivity of the following compounds towards a Grignard reagent?
$(I)$ $CH_3CHO$
$(II)$ $HCHO$
$(III)$ $CH_3COC_6H_5$

Mandelonitrile is obtained by the reaction between hydrogen cyanide and

In the reaction sequence: $CH_3-CHO$ $\xrightarrow{HCN, OH^{-}} (A)$ $\xrightarrow{H_2O/H^{+}, \Delta} \text{Product}$. The product will be: