When infants and very young children live in environments where they have no exposure or experience with language, their language development is severely impaired. This impairment is irreversible. Which of the following terms supports this explanation?

The correct answer is Sensitive periods of development.

Step-by-step Explanation:

1. Analyze the scenario described:
The question describes a situation where infants or very young children are completely deprived of language exposure and experience during their early years. As a result, their language development becomes severely and irreversibly impaired.

2. Evaluate the psychological/developmental concepts:
- Sensitive periods of development (sometimes referred to closely with critical periods) are windows of time in early life during which the brain is particularly receptive to certain kinds of environmental stimuli (such as language input). If the necessary input is not received during this developmental window, the neural pathways for that function fail to develop fully, leading to permanent or highly resistant deficits.
- Sociolinguistics is the study of how language is used in social contexts and how it varies based on social factors (e.g., class, gender, region). It does not explain biological developmental windows.
- Semantics refers to the branch of linguistics and logic concerned with meaning (e.g., the meaning of words, phrases, and sentences), which is a component of language rather than a developmental timeline.
- Nativism is the theory that certain skills or abilities (like language acquisition) are hardwired into the brain at birth. While nativism suggests humans have an innate capacity for language (like Chomsky's Language Acquisition Device), it does not directly define the specific developmental timeline or the permanent impairment caused by environmental deprivation in the way the concept of "sensitive periods" does.

3. Conclusion:
The observation that language deprivation early in life leads to irreversible impairment directly supports the concept of a sensitive period of development, during which exposure to language input is biologically essential for normal acquisition.