What does the given structural formula represent?

Which of the following is a class of $Bryophytes$?

Consider the following reaction: $C_6H_5NO_2$ $\xrightarrow{Sn/HCl} X$ $\xrightarrow{C_6H_5COCl} Y + HCl$. What is $Y$?

Ethanol,when reacted with $PCl_5$,gives $A$,$POCl_3$,and $HCl$. $A$ reacts with silver nitrite to form $B$ (major product) and $AgCl$. $A$ and $B$ are respectively:

Let $A$ and $B$ be subsets of a set $X$. Then

The $IUPAC$ name of the following compound is