Suppose You Suffer from Insomnia Because Your Body Has Shifted

Suppose you suffer from insomnia because your body has shifted to a schedule of going to sleep late and waking up late, and you cannot readjust to your normal time. What is one effective way to overcome this problem?

A) Keep trying to go to sleep at the normal time until your body resets its sleep schedule.
B) Go to sleep two hours later each night until you get around the clock to the normal time.
C) Eat a heavy meal just before going to bed.
D) Try going to sleep three hours earlier than usual for a few nights, and then the normal time.