In $Ulothrix$,meiosis $(Reduction\, division)$ occurs in:

Zygotic meiosis is a characteristic of .........

Which statement is correct for $Chlorophyceae$?

Sexual reproduction and mobile cells are absent in

$A.$ Algae are known as primitive plants.
$R.$ The body structure of algae is simple.

Consider the following statements:
$I$. They reproduce asexually by non-motile spores and sexually by non-motile gametes.
$II$. In this class,sexual reproduction is oogamous and accompanied by complex post-fertilisation developments.
$III$. The common members are $Polysiphonia$,$Porphyra$,$Gracilaria$ and $Gelidium$.
The above characteristics belong to which class of algae?