The mutation that would be passed on to living offspring if it happened in a parent is an insertion mutation in a gamete that deactivates a gene for hair color.
This is because gametes (sperm and egg cells) are reproductive cells that contribute to the genetic makeup of offspring. Mutations that occur in somatic (non-reproductive) cells, such as those leading to skin cancer, will not be passed on to offspring. Silent mutations do not affect the protein produced and would not typically result in a heritable trait if they occur in somatic cells. Conversely, mutations derived from gametes can be inherited by the next generation.