Answer:
Although I have been informed that these highly competitive positions are normally reserved for Special Agents with more experience than I have yet accumulated, I feel that my exceptional performance in the field warrants my consideration.
Step-by-step explanation:
This is the sentence that best describes Ms. Jackson's thesis. In this sentence, Ms. Jackson states her main purpose, which is convincing the reader that although the positions are normally reserved for agents with more experience, she has a performance that warrants consideration. The rest of her cover letter will ideally describe what this performance is and give more details that can convince the reader of her claim.