The correct answer is A — By looking for extra and unexpected symbols and characters in certain queries.

According to WGU Cybersecurity Architecture and Engineering (KFO1 / D488), SQL injection attacks often include malicious SQL code in input fields, with unusual symbols such as semicolons, apostrophes, or comments (', --, ;). Analysts detect these attacks by monitoring for unexpected or abnormal input patterns in database queries.

Changes to primary keys (B) and repeated login failures (C) are unrelated to SQLi detection. Administrative commands (D) relate more to privilege escalation.

Reference Extract from Study Guide:

"SQL injection attacks typically involve abnormal input that includes special SQL characters or commands; monitoring for such anomalies can reveal attempted injections."

— WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Application and Database Security Threats

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