Which of the Following Is/are the Minimum Performing Characteristics of Most

Which of the following is/are the minimum performing characteristics of most noninvasive ventilators?
1) Mandatory rate of 50 breaths/min or less
2) Inspiratory pressure of 30 cm H₂O or less
3) PEEP of 15 cm H₂O or less
4) Inspiratory flow of 180 L/min or less at 20 cm H₂O

A) 1 only
B) 1, 2, and 3 only
C) 1, 2, 3, and 4
D) 2, 3, and 4 only