Answer:
1. X + X
Explanation:
The sperm and the egg each carry half of the DNA for the zygote (which is one cell that eventually becomes a baby).
A normal human male has the sex chromosomes XY
A normal human female would have XX
If the Y chromosome is present, the result is a male.
If there either more or less than 2 sex-chromosomes, there is usually some sort of abnormality, like delayed development or the inability to mature and reproduce.
