Final answer:
The Sacramento River and the San Joaquin River are the two main rivers that flow into the San Francisco Bay, contributing to its biodiversity and climate moderation.
Step-by-step explanation:
The two rivers that flow into the San Francisco Bay are the Sacramento River and the San Joaquin River. These rivers are critical in delivering fresh water into the estuary, making the San Francisco Bay one of the most biologically productive regions with high biodiversity.
The bay acts as a natural moderator for local climates, such as the city of San Francisco, providing milder temperatures in both summer and winter compared to more inland areas like Sacramento.