Iodoform can be prepared from all except:

Given below are two statements :
Statement $I$ :
In Lucas test,primary,secondary and tertiary alcohols are distinguished on the basis of their reactivity with conc. $HCl + ZnCl_{2}$,known as Lucas Reagent.
Statement $II$ :
Primary alcohols are most reactive and immediately produce turbidity at room temperature on reaction with Lucas Reagent.
In the light of the above statements,choose the most appropriate answer from the options given below :

Which of the following compounds yields propanone upon dehydrogenation?

The reagent used to convert allyl alcohol to acrolein is:

The final product $A$,formed in the following reaction sequence is:
$Ph-CH=CH_2$ $\xrightarrow[\text{(iii) } HBr, \text{ (iv) } Mg, \text{ ether, then } HCHO / H_3O^{+}]{\text{(i) } BH_3, \text{ (ii) } H_2O_2, OH^{-}} A$

Product $[X]$ formed in the above reaction is :