Under what condition must outdoor household articles be inspected?

The correct answer pertains to the necessity of inspecting outdoor household articles specifically when they come from a federally regulated area. This requirement is largely due to the potential for these items to carry pests and diseases that may be harmful to the local environment or agriculture. Federally regulated areas are often designated because they have been identified as locations where certain pests or diseases are prevalent. Inspecting items from these areas helps in mitigating the risk of their introduction into new regions, thus safeguarding ecosystems and public health.

The other conditions mentioned may not systematically warrant inspection. For instance, simply entering a new state does not inherently pose the same risks as items arriving from a federally regulated area; thus, it does not mandate inspection. Additionally, just cleaning outdoor articles does not guarantee that they are free from pests or diseases, and therefore does not serve as a reliable condition for inspection. Similarly, the notion of inspecting only if items appear dirty is subjective and unreliable, as pests may be present regardless of the visual cleanliness of the items.