Answer:
The sentence that best adds dramatic tension is Option C: Drawing up a timetable for my exam preparations beforehand and revising lessons every day was my pathway to success, as I knew that my classmates were extremely competitive.
Step-by-step explanation:
Dramatic tension is an important part of any literature work or a film. It can be defined as excitement or an anticipation of the result of a story, for example, climax of a suspense novel. Dramatic tension can be loud or quite in nature. It may include surprises, mysteries, tasks, uncertainty.
In Option C, the writer mentions the tasks he is performing everyday to succeed in the exam because he knows that his classmates are extremely competitive. They arouse the curiosity of the outcome of the exam. The other options use words like, somewhat competitive, sort of competitive or fairly competitive for the classmates, which do not arouse dramatic tension like in Option C.