The best evidence to support the choice of sexual reproduction is:
Sexually, because each kitten looks different than the mother, which is a sign of genetic variation due to sexual reproduction.
This response highlights that the genetic variation observed in the kittens (different colors and patterns) indicates that they likely inherited genes from both the mother and a father, which is a characteristic of sexual reproduction. In contrast, asexual reproduction would typically result in offspring that are genetically identical to the parent.