Final answer:
The most vital question to ask a male patient before a digital rectal exam is if they are allergic to latex to prevent allergic reactions during the procedure. Ensuring patient safety is the immediate priority, followed by reviewing family medical history and addressing any current pain or symptoms.
Step-by-step explanation:
The most important question to ask a male patient getting a digital rectal exam is 'D. Are you allergic to latex?' While it is essential to address concerns like family history of cancer or personal discomfort during an examination, in the immediate context of conducting a digital rectal exam, confirming the patient's potential latex allergy is critical to ensure that no allergic reaction occurs due to the use of latex gloves during the procedure. Latex allergies can be severe, and thus, this precautionary question must be prioritized for patient safety. Additionally, obtaining a detailed history regarding cancer (such as prostate cancer) and discussing any current symptoms like pain are also important considerations but follow the latex allergy query.