Given below is a schematic representation of the phases/stages of the cell cycle. Which one of the following is the correct indication of the stage/phase in the cell cycle?

In ...$A$.... phase,there is synthesis of $RNAs$ and proteins that are needed for cell growth and replication of $DNA$. While it is ...$B$... phase,where synthesis of protein occurs that is needed for spindle formation and mitosis to continue.
Identify $A$ and $B$ to complete the given statement.

$S -$ Statement: The efficient size of the cell is maintained by meiosis.
$R -$ Reason: The specific type and fixed number of chromosomes are maintained in organisms generation after generation by mitosis.

Polytene chromosomes in salivary glands of Drosophila are formed as a result of

Statement $X$: During the process of meiosis,the genetic material replicates only once.
Statement $Y$: During interkinesis,there is no replication of genetic material.

Choose the correct option for the formation and disappearance of the bipolar spindle in a cell,respectively.