Explanation:
I think that every answer from your question is correct because the player who will do the serve can stand anywhere to serve the ball but the most important thing is that he should stand behind the end line. Your answers here are referring to that every service is done from the back and that is why I think those are all correct answers.
I hope that this information will help you to recognize the correct answer.
It would most likely lead to health problems if that is an answer
Parents should let them be curious and take adventures but limit them to a certain amount or how far they can go a day.
