What is the correct definition of menstruation? A. a doctor who specializes in female reproduction

B. a process for ovaries to release mature eggs

C. a joining of sperm and egg to form a fertilized egg

D. a breakdown in the lining of the uterus causing blood flow

Life expectancy in the united states is (76.4 for men and 81.1 for women). life expectancy is not the same as healthy life expectancy. healthy life expectancy is the number of years a person is expected to live in this number is obtained by subtracting years spent in poor health from overall life expectancy. the world health organization (who) calculates healthy life expectancy in 194 countries. the united states ranks twenty-ninth in the world using this measurement, with an average of of healthy life expectancy. singapore ranks number one (76 years), and japan is number two (75 years).