number 8 is b because when you eat plants or animals, it get transfred to glucose which is then transfered to atp. Think about it this way, when you are sick, you dont just go outside in the sun to recharge and then you suddenly get better, and energy, you have to rest and eat certain foods that will restore your ATP levles.
Small intestine is modified due to the presence of micro villi which has ability to increase it's size
