Collecting broodstock from the wild, breeding them in captivity, and releasing the young back into natural waterways for restoration would be a form of _____.

The scenario of collecting broodstock from the wild, breeding them in captivity, and then releasing the young back into natural waterways for restoration falls under the category of both aquaculture and fisheries. Aquaculture refers to the farming of aquatic organisms, which includes the breeding and rearing of species in controlled environments, typically with the intent of enhancing yields or supporting conservation efforts. In this case, breeding broodstock in captivity aligns with aquaculture practices.

On the other hand, fisheries management encompasses the sustainable harvesting and management of wild fish populations, which includes efforts aimed at restoring fish populations to their natural habitats. The act of releasing young fish back into natural waterways is consistent with fisheries practices focused on population restoration and conservation.

Thus, the chosen answer correctly identifies that the described activity integrates both aquaculture's traditional farming practices and fisheries' conservation efforts, making it a combination of both fields.