Can a man make a child at 100 years old?

Yes, a man can potentially father a child at 100 years old, as long as he is producing viable sperm. Unlike women, who have a finite number of eggs, men can continue to produce sperm throughout their lives, although sperm quality may decline with age. There have been documented cases of older men fathering children, but the risks of genetic mutations and health issues in offspring may increase with paternal age.