A societys infant mortality rate is an accepted indicator of that societys general health

A societys infant mortality rate is an accepted indicator of that societys general health status. Even though in some localities in the United vStates the rate is higher than in many developing countries, in the United States overall the rate has been steadily declining. This decline does not necessarily indicate, however, that babies in the United States are now, on the average, healthier at birth than they were in the past. Which one of the following reasons, if true, most strongly supports the claim made above about the implications of the decline？

A．The figure for infant mortality is compiled as an overall rate and thus masks deficiencies in particular localities.

B．Low birth weight is a contributing factor in more than half of the infant deaths in the United States.

C．The United States has been developing and has achieved extremely sophisticated technology for saving premature and low-birth-weight babies, most of whom require extended hospital stays.

D．In eleven states of the United States, the infant mortality rate declined last year.

E．Babies who do not receive adequate attention from a caregiver fail to thrive and so they gain weight slowly.

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