A computer science student needs to fill some information into a secured Adobe PDF job application that was received from a prospective employer. Instead of requesting a new document that allowed the

A man-in-the-middle attack intercepts live communication between two parties and does not involve attempting to crack a static document's encryption password.

Session hijacking involves stealing or forging an authenticated session token in a live network session, not attacking the encryption of an offline document.

A brute-force attack systematically tries every possible character combination without a predefined list, whereas using a specific wordlist of common passwords defines a dictionary attack.

A dictionary attack uses a precompiled list of likely or commonly used passwords to attempt authentication against a target. Unlike brute-force, it does not enumerate every possible combination but relies on the statistical likelihood that users choose predictable passwords. The student's explicit use of 'a list of commonly used passwords' precisely matches this definition.