Cyanohydrin of which of the following forms lactic acid?

Clemmensen reduction of ketones is carried out in

Organic products $A$ and $B$ are respectively -

What are $Y$ and $Z$ respectively in the given reaction sequence?

An organic compound $X$ is oxidised by using acidified $K_2Cr_2O_7$ solution. The product obtained reacts with phenyl hydrazine but does not give the silver mirror test. The compound $X$ is,

Which of the following will not give the iodoform test?