Concept:
Infant Mortality Rate (IMR) is an important indicator of the health conditions of a country. It measures the number of infants who die before reaching the age of one year for every 1000 live births in a given year.
Step 1: Understand the definition of Infant Mortality Rate.
Infant Mortality Rate refers to the number of deaths of infants under the age of one year per 1000 live births in a particular year.
Step 2: Identify the correct value.
Since the definition clearly mentions children who die before completing one year of age, the blank should be filled with:
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One
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Step 3: Select the correct option.
Therefore, the correct answer is Option (A).