Which of the following terms signifies a lack of speech due to psychological reasons?

The term that signifies a lack of speech due to psychological reasons is mutism. Mutism can occur when an individual is physically capable of speaking but chooses not to do so, often in response to psychological stress, trauma, or other emotional factors. This condition is distinct from other speech disorders because it fundamentally involves the absence of speech rather than a loss of the ability to produce language.

Nonverbalism generally refers to communication without words, often encompassing nonverbal cues like gestures or facial expressions, rather than a deliberate absence of speech. Aphasia involves language deficits due to brain injury or damage affecting language centers, leading to difficulties in speaking, understanding, reading, or writing but does not typically arise from psychological factors. Vocophobia, on the other hand, is an irrational fear of speaking, which could prevent speech but differs from mutism as it is driven by anxiety rather than a deliberate choice to refrain from speaking.