Infant Mortality Rate (IMR) is:

The correct answer is Option (2) → Number of deaths in a year per 1,000 live births of children

The Infant Mortality Rate (IMR) is the number of infants (children below one year of age) who die in a year for every 1,000 live births in that year. It is one of the main measures of a country’s health care, because babies in their first year are the most at risk; a falling IMR shows better care of mothers and newborns.