Answer:
a. Protagonist: Brian
b. Antagonist: society
c. Type of conflict: character vs. society
Step-by-step explanation:
The protagonist of a story is the main character, the one who is involved with the central theme and the main activities of the plot. As you can see, after reading the text shown in the question aciam, Brian is the only character quoted who is involved in the main conflict of the plot, so Brian is the protagonist.
The antagonist is the character or group of characters that hinders the protagonist from fulfilling his desires. In the case of the text above, we can see that society in the city of Brian prevents him from having a dog, and can even kill the dog if someone find out. In this case, society is the villain.
When a character needs to face a society to achieve the goals he has, the narrative presents a conflict called the character vs. society, where a character literally has to fight against society.