Which of the following combinations of sex chromosomes produce a male child: XX or XY?

The Combination XY produces a male child. The unfertilized egg has one X chromosome. The sperm either has a X chromosome or a Y chromosome. Male child will be produced if sperm carrying Y chromosome fertilizes with the egg. Female child will be produced if sperm carrying X chromosome fertilized with the egg. Therefore, combination XY will produce a male child.