This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infection, Subject name: Medicine
An 18-year-old woman visits her physician because of 3 weeks of malaise, 2 weeks of fever, and a sore throat. Physical examination shows pharyngeal infection with enlarged tonsils and a patchy, white exudate; enlarged, palpable anterior and posterior cervical, axillary, and inguinal lymph nodes; tenderness in the right upper quadrant; and minimal splenomegaly. Laboratory data show hemoglobin 14 g/dL; hematocrit 42%; platelets 380,000/mL; WBC 8500/mL, with 35% segmented neutrophils, 1% eosinophils, and 64% lymphocytes, of which 36% were atypical. Which of the following is the most likely diagnosis? 
Select and explain. 
A. infectious hepatitis, B. lymphocytic leukemia, C. infectious mononucleosis, D. Hodgkin's disease
C: infectious mononucleosis
Answer: C: infectious mononucleosis 
Explanation: Infectious mononucleosis is an acute, self-limited infection of the lymphatic system by the EBV. Typical infectious mononucleosis has an incubation period of 4-8 weeks. The prodrome includes malaise, anorexia, and chills, and then the classic symptoms of pharyngitis, fever, and lymphadenopathy develop. Headache is also common.