After examining a 14 years old child, doctors told the parents that their child is suffering from a chromosomal abnormality which is usually caused by nondisjunction of chromosomes. Which among the following chromosomal abnormalities, the child must be suffering from?

Klinefelters syndrome is usually caused by nondisjunction of chromosomes. Nondisjunction happens when a pair of sex chromosomes fails to separate during egg (or sperm) formation. When an egg (or sperm) with an extra X chromosomes joins with a normal sperm (or egg), the resulting embryo will end up with three sex chromosomes (XXY) instead of the normal two (XX or XY). As the baby develops, the extra chromosome is then copied in every cell.