German measles virus (rubella), a common cause of exanthema in children, is best described by which of the following statements
A. Measles (rubeola) and German measles (rubella) are caused by the same virus
B. Incubation time is approximately 3 to 4 weeks
C. Vesicular rashes are characteristic
D. Onset is abrupt with cough, coryza, and fever
E. Specific antibody in the serum does not prevent disease