Final answer:
The National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC) are the two governmental agencies funded by congressional appropriations. The correct answer is option a).
Step-by-step explanation:
Two governmental agencies that are funded by congressional appropriations (tax dollars) are the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC). These agencies receive funding from Congress to carry out their respective missions.
The NIH is responsible for conducting medical research to improve health and save lives, while the CDC focuses on protecting the public from diseases and injuries.