Final answer:
When entering a roundabout, wait for an adequate and safe gap in traffic before proceeding.
Step-by-step explanation:
When entering a roundabout, you should wait for an adequate and safe gap in traffic before proceeding, which is option 1. Unlike traditional intersections, roundabouts operate on the principle of yielding rather than having the right-of-way. This means that you need to give way to vehicles already in the roundabout before entering.