The heimlich maneuver is a series of pushing motions on the area just under the diaphragm that a person whose airway is blocked. which best explains how this maneuver unblock a person's airway?

Pushing the diaphragm causes air to flow out of the lungs, which pushes the blockage out.

Explanation:

Every year, various people die due to choking on objects, which blocks their airways and leads to suffocation. Choking is one of the leading causes of unintentional death in the United States. However, there is a basic method that can be utilized to remove the trapped object or unblock the airways of the individual. The method or the technique is termed as the abdominal thrusts or the Heimlich maneuver.  

This technique helps to lift the diaphragm and expel the air from the lungs, that is, it helps to remove the blockage of the airways.  

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

thinking it would be physical characteristics