<prompt> Which of the following is true about Pneumothorax?Decreased Chest ExpansionIncreased Breath SoundsIncreased Vocal ResonanceDull percussion note  <response>: Answer is A Decreased Chest Expansion: Chest Expansion may be Normal or Decreased in Pneumothorax. Pneumothorax is associated with reduced breath sounds, reduced vocal resonance, hyper-resonant percussion note and tracheal detionmediastinal shift to opposite side. 