The first was an old tv repair shop called b’s tvs—a shack, mostly, where the tenant sat inside smoking cigars, waiting for customers to trigger the front door’s buzzing optical alarm like flies in a bug zapper.

it illustrates that the optical door alarm is annoying.
it suggests that the tenant doesn’t want customers.
it shows that the tenant takes advantage of people.
it conveys the idea that the tv repair shop is uninviting.

In this paragraph:

The first was an old TV repair shop called B’s TVs—a shack, mostly, where the tenant sat inside smoking cigars, waiting for customers to trigger the front door’s buzzing optical alarm like flies in a bug zapper.

The author

Conveys the idea that the TV repair shop is uninviting.

Explanation:

To understand this answer we need to analyze it carefully. First of all, with "a" option. The author never mentions something annoying. That is a perspective claim, however, in our paragraph, we have only descriptions. B option talks about the tenant not wanting customers. However, the most logical idea would be to keep the store closed. So it is incorrect. C option talks about the tenant taking advantage of people, however, the description includes no abusive scene. Nevertheless, we do found the scene very polluted. Which guides us to an idea of a very disturbing environment.

most likely the answer would be a.) cupidity

definitions:

cupidity - greed for money or possessions

hydrophobia - extreme or irrational fear of water, especially as a symptom of rabies in humans

pathology - the science of the causes and effects of diseases, especially the branch of medicine that deals with the laboratory examination of samples of body tissue for diagnostic or forensic

patho -   relating to disease