1.If someone is choking, you should ... a) hit them on the back ​b) lean them backwards ​c) lie them on their side

If someone is choking, the appropriate action is a) hit them on the back. Specifically, you should perform back blows between the shoulder blades while they are leaning forward. If that does not resolve the choking, you can then perform abdominal thrusts (Heimlich maneuver) if you are trained to do so. Always seek emergency help if the situation does not resolve quickly.