Please Read the Clinical Scenario, and Then Answer the Question

Please read the clinical scenario, and then answer the question that follow to become familiar with the traditional NCLEX question format.
About 5 days ago, a 45-year-old patient began experiencing symptoms of what appeared to be a simple upper respiratory tract infection. She has come to the ER after experiencing mild paralysis in her arms and an abnormal heartbeat. While in triage, she suddenly develops difficulty breathing and is sent up to the respiratory unit where you are the charge nurse. In your initial assessment, you discover gross inflammation of her pharynx and tonsils, and the entire area appears to be covered by a grayish-white membrane. You order a throat swab and additional specimens for microbial analysis, and you immediately send the patient into isolation.
-You inform the patient of her condition and tell her that the symptoms she developed were so severe due to the pathogen's production of an exotoxin.In explaining the role of exotoxin in the pathogenesis of her disease,you correctly state that the exotoxin

A) is encoded by the bacterium's own genetic material (DNA) .
B) is encoded by a prion of the bacterium.
C) is encoded by a bacteriophage of the bacterium.
D) is encoded by a retrovirus of the bacterium.