What types of payloads may rockets flown at Tripoli launches carry?

Rockets flown at Tripoli launches may carry hazardous payloads because Tripoli Rocketry Association has specific guidelines that permit the transportation of certain types of payloads under controlled conditions. These payloads can include those classified as potentially hazardous, such as poisonous, flammable, incendiary, or explosive materials, as long as they meet safety protocols and regulations established by Tripoli and relevant authorities.

The ability to carry hazardous payloads is balanced by strict safety measures to ensure that launches are conducted safely and responsibly. This embraces the spirit of rocketry experimentation and development while prioritizing the safety of participants and spectators alike.

The other options do not align with Tripoli's guidelines or the overarching safety considerations implemented during rocket launches. For instance, while vertebrate animals may be used in research contexts, there are stringent rules concerning their treatment and safety that restrict their inclusion in standard payloads at launches. Similarly, restricting payloads solely to vegetable substances does not reflect the broader spectrum of permissible payloads that are subject to safety oversight. Therefore, the correct choice highlights the comprehensive approach Tripoli takes towards safety and experimentation in rocketry.