Given the question: Sleepwalking is a sleep disorder. Your child will rise from bed and walk or engage in other activities that they would normally do when they are awake. Their eyes will be open but they will appear to be in a dream-like state, and will probably not answer when you talk to them, although they may carry out conversations. Sleepwalking can last a few seconds , a few minutes, or more. Sleepwalking can be an indication that certain parts of the brain may not be relaxing properly at bedtime. It can be caused by illness or fever, tiredness, stress or anxiety. It is thought to occur in the beginning, slow-wave stages of non-rapid eye movement sleep before dream sleep. It may be related to the lack of magnesium , and it is very possible that hormonal changes in body could cause it. Certainly a child is more likely to be a sleepwalker if one of his parents suffered, too . Sleepwalking itself is not dangerous and is generally not a sign of any more worrying problems. But if your child sleepwalks regularly, you have to take safety measures to make sure that he doesn't hurt himself while sleepwalking. Makes sure that any doors can't be opened by a child, and lock doors to the cellar, kitchen and other dangerous places. Check each night before lights go out for sharp objects or, indeed , anything on the floor which your child could trip over or hurt himself on. A child may sleepwalk once and never sleepwalk again. Others may sleepwalk once a month or so. Still others may sleepwalk almost nightly. If you are worried you should consult your doctor. It can be inferred from the passage that _ . A) sleepwalking may be passed down in a family B) drugs that could cure sleepwalking have been developed C) during a normal sleep, a person never opens his eyes D) most doctors consider sleepwalking as a serious problem
The answer is:
A