Initial clues about the genetic/chromosomal mechanism of sex determination can be traced back to some of the experiments carried out in:

Genetic identity of a human male is determined by

The formation of a male child depends on the sperms because

$ZW-ZZ$ type of sex determination is seen in . . . . . . .

$A$ male child will be born if:

Given below are two statements.
Statement $I$ - $X$ Chromosome has a large amount of euchromatin and a small amount of heterochromatin.
Statement $II$ - The homologous region of the $X$ Chromosome contains a smaller number of genes than the $Y$ Chromosome.
In the light of the above statements,select the correct option given below: