Which of the following statements is true about the epidemiological determinants of measles -: (A) Measles virus survives outside the human body for 5 days, (B) Carriers are important sources of infection, (C) Secondary attack is less than that of rubella, (D) Incidence of measles is more in males than females
Answer is C. SAR of some important infectious diseases

Measles → 80% 
Rubella → 90 - 95% 
Chickenpox → 90%
Pertussis → 90%
Mumps → 86%