Final answer:
The best course of action for a jellyfish sting is to rinse the injury with seawater, apply vinegar, and seek medical attention.
Step-by-step explanation:
In the case of a jellyfish sting, it is important to remember that peeing on the affected area is not an effective treatment. The best course of action is to rinse the injury with seawater to remove any tentacles and apply vinegar to neutralize the venom. Additionally, seek medical attention as soon as possible as some jellyfish stings can be severe.