Read the paragraph. Read the question and choose the correct answer.
Lack of sleep can affect growth and the immune system. You can become sick more easily and take longer to heal from colds, flu, injuries, and other illnesses. Although scientists don't completely understand everything about sleep, they think that most people have typical sleep, which includes four stages or cycles.
Which statement is FALSE, according to the text?

• Your lack of sleep can have a negative impact on your growth and your immune system.
• Scientists haven't explored all of the properties of sleep.
• Your lack of sleep is able to boost your immune system.
• Typical sleep has four stages.