Filiform apparatus is a characteristic feature of

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:

Choose the correct sentence$(s)$.
$(I)$ Nucleus of the functional megaspore divides meiotically to form two nuclei.
$(II)$ After the $8$-nucleate stage,cell walls are laid down leading to the organization of a typical female gametophyte.
$(III)$ The egg apparatus consists of two synergids and one egg cell.
$(IV)$ Three cells at the chalaza end are called antipodal cells.

Filiform apparatus is a feature of

Which of the following is not found in the embryo sac of a dicotyledonous plant?

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