Pyrolysis of acetone gives $CH_2=C=O$ called

The compounds $A$ and $B$ are respectively

Which reagent is used to distinguish between acetaldehyde and acetophenone?

When an oxime is treated with trifluoroperoxyacetic acid,it yields:

In the given reaction :
$CH_3CHO$ $\xrightarrow[(i) \ NaCN/HCl]{(ii) \ H_2O/H^{\oplus}/\Delta} (A)$ $\xrightarrow[reagent]{Fenton} (B)$
$(B)$ will be :

In the given reaction $C_6H_5CHO + X \xrightarrow{(i) Zn, (ii) HOH/NH_4Cl} C_6H_5-CH(OH)-CH_2-COOC_2H_5$,$[X]$ will be: