We have to consider that all species share a different percentage of the DNA between them in terms of how it resembles in these different organisms, which varies depending on if the species are more or less related to each other. This amount of resemblance in the DNA is higher in cases of twins, for example. Having this clear, the correct answer to this question is the last one (none of the above): Blanche doesn't have the exact same genome as her cousin, neither as her best friend, nor as her sister, unless they both were twins.