Answer:
A. The three boarders.
Step-by-step explanation:
Franz Kafka's "The Metamorphosis" is an allegorical story of a young man's transformation into a bug, rendering him useless and helpless, and eventually dies. This story deals with themes of isolation, aloofness, responsibility, alienation, pressure, etc.
In the short story, the major characters are the residents of the house where Gregor and his family live. His father, mother, and sister constitute the primary characters to Gregor Samsa's main character. Added to that are the three boarders that his mother took in to get extra money after Gregor became an insect and can't work anymore. They represent the intolerant attitude of society, a representation of the outside world.
The three bearded gentlemen seemed repulsed and detest Gregor when they saw he was an insect. Stating that they loved cleanliness, they mostly took their meals inside their room and even invited Grete Samsa to play the violin inside their room "where it is, after all, much more cozy and comfortable[?]"
Their reaction and behavior towards the Samsa family not only showed their callousness, but they also demanded that they will move out and not pay rent after spotting Gregor.
Thus, the correct answer is option A.