How many core biosafety work practices are there according to the National Research Council's guidelines?

The correct choice reflects that there are seven core biosafety work practices outlined in the National Research Council's guidelines. These practices are fundamental for ensuring safety in laboratories that handle biological materials. They are designed to address common risks associated with the use of biohazardous agents and establish a framework for minimizing exposure and accidents.

Adopting all seven practices fosters a culture of safety, encourages responsible research conduct, and enhances preparedness to handle potential biological hazards effectively. Each practice is integral to forming a comprehensive biosafety program, ensuring that research environments remain safe for both personnel and the surrounding community.