Neighborhood density describes words that differ by one phoneme.

• A. Phonotactic probability
• B. Neighborhood density
• C. Word frequency
• D. Independent analysis

Answer: (B)

The key idea here is neighborhood density, which measures how many real words are phonologically close to a target word. Neighbors are words that differ by exactly one phoneme from the target, often by substituting a single phoneme while keeping the rest of the sounds in the same order. So a word with many such one-phoneme variants has a dense neighborhood, while a word with few variants has a sparse neighborhood. This concept helps researchers understand how quickly or home in on a word during listening or production, since many close neighbors can create more competition or more activation during retrieval. Phonotactic probability is about how likely a sound sequence is in the language, word frequency is how often the word is used, and independent analysis isn’t a standard term in this context. Therefore, the description fits neighborhood density.