Is captive breeding the Best way to save endangered species?

The threats facing each endangered species are different. Additionally, some species are relatively easy to care for in captivity and reproduce frequently while others rarely survive and/or don't reproduce in captivity. Captive tigers, for example, already outnumber wild tigers, and this means they are unlikely to go completely extinct, even if none are left in the wild (which would be terrible). However, there are tens of thousands of endangered species, and humans can't possibly maintain viable populations of all of them in captivity. For the vast majority of species, the only way to save them is to preserve their habitats and to eliminate the pollution, hunting, or whatever else threatens them. So captive breeding is not the best option to save endangered species, but it can make a big difference in cases where it is possible.