The Single Most Important Cause of Improvement in Child Survival

question 14

Short Answer

The single most important cause of improvement in child survival in the twentieth century is _____.

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Definitions:

Filter

A device or process that removes impurities or separates particles from a liquid or gas.

Engulf

To surround or envelop completely, often used to describe how one cell can consume another.

Terrestrial Mollusks

Mollusks that live on land rather than in the sea or freshwater bodies; this group includes snails and slugs.

Gastropods

A class of mollusks typically having a one-piece coiled shell and including snails, slugs, and whelks, which are primarily marine, but also found in freshwater and terrestrial environments.