All the following are controlled mode of mechanical ventilation EXCEPT

(A). Except the option A all other forms of mechanical ventilation variables are controlled either fully by the machine as in options B and C which need to paralyze the patient to get the synchrony or partially as in options D and E where there is patient trigger by an effort to respiration followed by the machine active work to do the preset ventilation values; ventilatorpatient asynchrony can occur in this mode also because tidal volume, inflation pressure, and inspiratory time are determined by the ventilator alone. PSV allows the patient to control as much of the rate, tidal volume, and inspiratory time as much as possible. It is considered a gentler form of mechanical ventilation and is designed for patients with relatively minor lung disease or for those with neuromuscular weakness.