Mutations can occur before, during, and after mitosis and meiosis. If a mutation occurs in cells that will make gametes by meiosis or during meiosis itself, it can be passed on to offspring and contribute to genetic variability of the population
B. Half of the total genetic information
In determining species, it is best to differentiate in terms of the population that is being adapted in which, a certain niche. So, if it has a small gene pool, and the different species will be interbreeding each other with a much genetic variability in gene pool, it would most likely cause a less adaptation. The niche will be having a less adaptation if too much genetic variability will occur.
That looks about right to me