Read the short text. Read the question and choose the correct answer.

Stage two is your slightly deeper sleep as your brain sends signals to your muscles to relax, and your heartbeats slow down. Breathing slows down, and a body's temperature drops as eye movement stops. Brain waves slow down with an occasional burst of rapid brain waves. This stage usually lasts about 20 minutes, and it begins to become harder to awaken. About 45% of your night is stage two of sleep.

What statement is true, according to the text?

• Stage two can continue for 20 minutes.
• Stage two isn't your deep sleep.
• Stage two is the main part of your sleep.
• During stage two of sleep, your body temperature can increase.