The author is using B. INDIRECT CHARACTERIZATION.
Indirect Characterization refers to what the character says or does. In the above passage, the author wrote what the character does. We, as the readers, only infer what the character is all about because we cannot read his mind or "get inside his head".
Direct Characterization refers to what the narrator directly says or thinks about the character. The reader is told what the character is like.
A cover letter is a document you send with your resume, that provides additional information about skills and experiences related to the job you are applying to.
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