Which of the following is a condition under which a person under 18 can use an air weapon?

A person under 18 can use an air weapon for sporting purposes due to specific legal allowances made for minors engaging in organized shooting sports. This reflects a regulated and supervised environment where young individuals can participate in structured activities while adhering to safety standards and guidelines. Sporting purposes often include settings like clubs or competitions where the use of such weapons is deemed appropriate and safe under adult supervision.

The other options typically do not align with legal regulations regarding air weapon use by minors. For home defense and personal protection, the law generally imposes stricter criteria that are not typically met by youths under 18 years of age. Similarly, hunting has its own legal restrictions and considerations, and in most jurisdictions, it requires specific permits and age qualifications that exceed what is permissible for a minor using an air weapon.