In humans, the sex of the baby is determined:

1. At the time of fertilization and by the father

2. At the time of fertilization and by the mother

3. At the time of implantation and by the father

4. At the time of implantation and by the mother

In the male human being, sperms contain autosomes and

1. Only one Y-chromosome

2. Only one X-chromosome

3. Both X and Y-chromosome

4. Either X or Y-chromosome