Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to motivate an autistic teen or adult to exercise [title] Make sure the exercise environment is calm and natural. [step] During exercise, the surrounding environment should be calm and devoid of noise or distractions. There should be no disturbances and the environment should be pleasant.

Ending1: At the same time, you should make sure the environment is peaceful and restful without disruptions, sudden movements, or pollutants. [substeps] If you experience a low stress or comfort level, the exercise process may lead to irritations and other disruptions. Ending2: [substeps] The water should not be too hot and/or too cold. There should be no tv, phones, and computers in the exercise area or where the child should be sitting. Ending3: [substeps] Also, there should be no crowds nearby, because this can make autistic individuals confused and worried. A natural environment with plants, greenery and fresh air works best. Ending4: [substeps] Before you begin the exercise routine and start moving around in the stationary position, take out your earbuds. Continue your walking walk around your neighborhood while walking through all your neighborhood's parks, sports fields, and other natural places.

Answer format: ending1/ending2/ending3/ending4