I believe the answer is <span> the social exchange theory
</span><span> the social exchange theory is based on the assumption that all people are individualistic in nature.
</span>This theory believes that human only choose to interact with another human only if the benefit from interacting with that other human surpass the cost to interact with him. (which explains the reason some people choose to marry old -rich individuals despite negative perception that will be labeled to them)
They can engage in l<span>arge numbers of people and make complex plans for some future undertaking. Symbolic interraction refers to a form of communication without any sound which rely solely on gesture. For example, you can communicate with a lot of people to be silent by putting your finger in front of your mouth.</span>
