What was a primary source of food for the Pacific Coast tribes?

The primary source of food for the Pacific Coast tribes was indeed fish and deer. Tribes located along the Pacific Coast, such as the Chinook and Coast Salish, had access to abundant marine resources. They relied heavily on fishing for sustenance, particularly salmon, which formed a cornerstone of their diet and cultural practices. In addition to fish, these tribes also hunted deer, which provided meat and other resources. The availability of these food sources was significantly influenced by the coastal environment, allowing these communities to develop sophisticated methods of fishing and hunting.

The other food sources mentioned in the other choices are not as relevant to the Pacific Coast tribes. Buffalo, for instance, were more characteristic of the Great Plains tribes, while corn and beans were staples for Native American communities in the agricultural regions, particularly in the Southwest. Caribou and seals, on the other hand, are primarily associated with Arctic and subarctic tribes, not those dwelling along the Pacific Coast.