For pollinated ovary which is correct

In angiosperms, the following events occur during megasporogenesis and megagametogenesis

$(i)$ Differentiation of megaspore mother cells

$(ii)$ Meiosis of the megaspore mother cell

$(iii)$ Formation of a linear tetrad

$(iv)$ Mitotic division of the functional megaspore

$(v)$ Degeneration of 3 megaspores

$(vi)$ Formation of embryo sac

$(vii)$ Fusion of polar nuclei

The correct sequence is

$A$ : Filiform apparatus guides the pollen tube into the synergids.
$R$ : It is special cellular thickening at micropylar tip to secrete chemotropic stimulus.

The number of mitotic generations required to form a mature embryo sac in most of the flowering plants is

Synergids of the polygonum type embryo sac are

 The number of embryo sac in an ovule is generally