Which of the following compounds does not give the iodoform test?

Which of the following reactions gives a product with a $C=N-N$ linkage and a yellow precipitate?

Which statement is incorrect for the given reaction sequence: $CH_3-CN$ $\xrightarrow[(2) H_2O]{(1) CH_3MgBr} X$ $\xrightarrow{2,4-DNP} Y$?

Given below are two statements $:$
Statement $(I) :$ Vanillin,with the structure shown below,will react with $NaOH$ and also with Tollen's reagent.
Statement $(II) :$ Vanillin will undergo self-aldol condensation very easily.
In the light of the above statements,choose the most appropriate answer from the options given below $:$

The product $(B)$ is:

The products of acid hydrolysis of $P$ and $Q$ can be distinguished by:
$P = H_2C=C(CH_3)(OCOCH_3)$
$Q = H_3C-CH=CH(OCOCH_3)$