3 d is the correct answer but I am not sure about answer 4 I think the answer should be ans4d because Your kidneys remove wastes and extra fluid from your body. Your kidneys also remove acid that is produced by the cells of your body and maintain a healthy balance of water, salts, and minerals—such as sodium, calcium, phosphorus, and potassium—in your blood. That helps it to stay balance
Yes they do it is they're sworn duty to help those in need, here's a better example if you were driving by the car crash would you drive past it and stare at those in need or would you go and help the injured person/people in the car wreck.
