Which one is the female gametophyte in angiosperms?

The arrangement of nuclei in a typical angiosperm embryo sac is ......... .

Given below are two statements: One is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A):$ $A$ typical unfertilised,angiosperm embryo sac at maturity is $8$-nucleate and $7$-celled.
Reason $(R):$ The egg apparatus has $2$ polar nuclei.
In the light of the above statements,choose the correct answer from the options given below:

$.......$ embryo sac is an $8$-nucleate structure.

In a majority of flowering plants,out of the four megaspores,........ megaspores degenerate and ........ megaspore remains functional.

What do '$d$' and '$e$' represent in the given figure?