What is true about all neurons?
a-they are bundled together in nerves that are surrounded by a protective sheath.
b-they all transmit signals through axons and receive neurotransmitters through dendrites.
c-they each bring nutrients to the brain and produce a fatty protective layer called myelin.
d-they all send signals from the brain to the body through long axons in the vertebral column

Andrew feels good about himself. he doesn't know exactly why he is so happy, but every day he looks forward to his schoolwork and chores. "i play a game," he says. "i make a list of everything i have to get done, and then i try to finish it all before a certain time. for some reason, i feel great when i beat my time." based on this information, why is andrew happy? he gets a proper amount of sleep he eats healthy meals he has a strong family support group he regularly meets his own goals