What best describes the naming explosion?

The naming explosion refers to a significant and rapid increase in an infant's vocabulary, particularly emphasizing the acquisition of nouns. This phenomenon typically occurs between the ages of 18 months and 2 years, when toddlers begin to develop more robust language skills and show a marked interest in naming objects, people, and concepts in their environment. During this period, children often learn new words at an accelerated pace, which leads to a noticeable expansion of their vocabulary.

This phase is critical in language development as it lays the groundwork for more complex language use in the future. The naming explosion not only involves learning new words but also reflects an increasing cognitive ability to categorize and label their experiences, which is essential for meaningful communication and social interaction.

In contrast, the other options do not capture the essence of this rapid vocabulary increase. While a gradual increase in sentence complexity or an expansion of grammatical understanding could occur later in language development, these do not specifically define the naming explosion. Similarly, a sudden decrease in vocabulary does not accurately relate to this concept, as the naming explosion is characterized by growth rather than reduction.