单选题 A client with hepatitis A expresses concern that his friends may also acquire hepatitis. Which of the following is most commonly used for prophylactic treatment of people exposed to hepatitis A?
A. Penicillin.
B. Sulfadiazine (Microsulfon).
C. Immune serum globulin.
D. Interferon.

【正确答案】 C

【答案解析】Immune serum globulin is administered prophylactically to people exposed to hepatitis A. Hepatitis A vaccine (Vaqta) may be used in conjunction with immune globulin for immediate and long-term protection.