Which condition is essential to maintain sufficient intraoral air pressure for the production of fricatives such as /f/?

• A. Velopharyngeal closure
• B. Velopharyngeal port open
• C. Lips loosely closed
• D. Tongue tip contacting teeth lightly

Answer: (A)

Maintaining intraoral air pressure for fricatives like /f/ depends on preventing air from leaking into the nasal cavity. This happens when the velopharyngeal port is closed, so the airstream stays in the oral cavity as it passes through the narrow labiodental constriction formed by the lower lip and upper teeth. If the port were open, air would escape through the nose, lowering pressure and weakening the turbulent frication that defines the sound. The essential factor is velopharyngeal closure. Lip position and tongue involvement matter for shaping the sound, but they don’t guarantee the necessary oral pressure if air can escape nasally.