Synapsis occurs in which phase of meiosis?

The simultaneous splitting of the centromere of each chromosome allowing them to move toward opposite poles of the cell is a change shown in......

$A$ : Anaphase-$I$ is the actual phase of reduction in the number of chromosomes.
$R$ : Homologous chromosomes move to the opposite poles with both their chromatids.

Bivalents in meiosis are

Which of the following stages of meiosis is responsible for deciding the genetic constitution of gametes?

When a pair of homologous chromosomes (bivalent) is formed,it consists of: