When should Form 577 and 579 be used for processed plants?

Form 577 and Form 579 are essential documents in the context of phytosanitary exports and serve to ensure that processed plant products comply with various regulatory requirements. The correct answer emphasizes that these forms should be utilized when all eligibility conditions are met. This means that the processed plant products must fulfill specific criteria, such as health standards and origin requirements, before they can be processed and exported.

By utilizing these forms when all conditions are satisfied, the exporting entity demonstrates due diligence in adhering to phytosanitary regulations, thus facilitating smoother trade and reducing the risk of biological threats. This ensures that the processed plants entering a foreign market do not pose a risk to agricultural health in the importing country.

The other options relate to specific scenarios that do not align with the necessary conditions for using Form 577 and Form 579. Therefore, only the choice stating that these forms should be used when all eligibility conditions are met captures the essential requirement for compliance with phytosanitary regulations.