To positively affect the Amur leopard population through biotechnology, the most effective approach would be:
By providing a way to clone and reproduce Amur leopards to prevent their extinction.
Cloning and other reproductive technologies can help increase the genetic diversity and population size of critically endangered species, which is essential for their survival. The other options, such as spontaneous generation or breeding with other cat species, may not effectively or ethically support the goal of preserving the Amur leopard.