A person who is responsible for pesticide containers must:

The correct answer emphasizes the importance of security and control over pesticide containers to prevent unauthorized access and potential misuse. Storing pesticide containers in a locked enclosure or having a responsible person maintain control over them at all times ensures that only trained and authorized individuals can access these potentially hazardous materials. This practice is crucial for safety, as it minimizes the risk of spills, leaks, or accidental exposure that could occur if the containers are left unattended or accessible to untrained individuals.

While the other options provide some level of safety, they do not address the central issue of controlling access to the containers. Keeping containers off the ground in a vehicle does not prevent unauthorized access, as they could still be tampered with. Likewise, covering containers with a tarp does not provide adequate security and may not protect against spills or environmental factors. Finally, keeping containers on application equipment could lead to situations where they are left unattended, posing similar security risks. Thus, the best practice is to ensure a secure and controlled environment for pesticide container storage.