Dreams The Average Adult Spends Almost Two Full Hours Every Night

Dreams
The average adult spends almost two full hours every night dreaming. Dreams mainly occur during a period known as REM (Rapid Eye Movement) sleep. While you are in REM sleep, your brain is very active-almost as active as if you were awake. The fact that we dream most often during REM sleep is one of very few facts about dreams that every scientist agrees on. Scientists do not know exactly which portion of the brain creates dreams or even why we have them in the first place.
One theory about their purpose is that dreaming helps the brain to organize and store memories. As your body relaxes, your brain processes all of the information it received during the day. While you sleep, your brain organizes the information into memories; your mind perceives this process as dreaming. Because your mind works differently when you are asleep than it does when you are awake, your dreams may seem confusing, illogical, or just downright silly.
Another theory is that dreams allow your mind to work out difficult problems that you encounter while you are awake. The unrealistic, free-flowing nature of dreams allows your mind to consider the problems in creative ways that you would likely never think of during your waking hours. Still other scientists believe that dreams are random events with no real function. According to this theory, there is no actual reason for dreaming-it is simply what happens when you go to sleep.
As you can see, there is no scientific consensus about how or why we dream. There are many different theories, but no proven answers. Until then, you might as well just enjoy the fantastic nighttime adventures you get to go on without ever leaving your bed.
Question: What is the best summary for the passage?

A) Scientists agree that dreaming occurs during REM sleep. However, they argue whether dreams help us remember, help us solve problems, or serve no function at all.
B) People dream during the REM stage of sleep. But after a great deal of research, scientists now generally agree that we will never know why we actually dream.
C) The brain is quite active during REM sleep. It is during this stage of sleep that humans dream the most-nearly two hours a night for the average adult.
D) While scientists agree on when we dream, some argue that dream help us remember things while others suggest dreams have no purpose at all.