Final answer:
The CDC is the federal agency responsible for monitoring health precautions for international travelers, managing notifiable disease surveillance, and publishing data to safeguard public health. So, the correct answer is option a.
Step-by-step explanation:
The federal agency that monitors health precautions for international travelers is the Centers for Disease Control and Prevention (CDC).
The CDC plays a critical role in protecting public health, including the health of international travelers. It collects data on notifiable diseases through the National Notifiable Diseases Surveillance System (NNDSS) and regularly publishes this data to inform and protect the public.
Therefore, option a is the correct answer to the question.