Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to swim laps [title] Observe pool rules. [step] Each pool has a different set of rules. Most pools don't allow diving or running, and many sports pools ask you to shower before entering.

Ending1: These rules might vary from one sports facility to another. [substeps] Be mindful that swimming laps might not be as authentic as other swimming laps, as swimming simply means carefully washing and drying your body after your swim laps. Ending2: If you swim at a pool with signs over the lanes saying " slow, " " medium, " or " fast, " make sure you choose the correct lane for your workout. If you're a beginner, choose the slow lane. Ending3: This means that you aren't able to swim laps in a pool that accepts human bodies under the water. On the other hand, some pools may have additional rules that you'll need to interact with in order to swim laps freely. Ending4: These rules include things like : [substeps] Not swimming in chlorinated pools as they are unsafe and dangerous. Not swimming in pools with slippery slides, etc.

Answer format: ending1/ending2/ending3/ending4