What is the second link in the chain of transmission?

"The reservoir or the body in which the pathogen lives or stays inside"

Explanation:

The Chain of transmission:

A pathogen or any foreign particle having the ability to develop inside a living organism goes through a series of steps or through a set of sequences to survive or carry on its activities inside the given host body.

As we can number the steps or sequence which is followed by the pathogenic body to develop itself,which are as follows:

when in a crucial situation, after calling 911, the correct posture for delivering effective compression is the proper hand placement.

first, place two fingers at the sternum, then put the heel of your other hand next to the fingers and place hand on top of the other. lock your elbows by using your body’s weight and compress the victim’s chest with a depth of 2 inches.

moreover, do 15 compression and 2 breaths, this process must be done four times until there is a pulse or a arrive.