adjust flow rate to keep the reservoir bag inflated
ensure that the reservoir bag is not kinked or twisted
ensure that valves open during expiration and close on inhalation
Number 3 is correct.
Rationale: If the reservoir bag kinks or twists, the client can suffocate. The mask should fit snugly on the face to avoid loss of oxygen. The flow rate should be adjusted to keep the bag inflated. A properly working mask will have valves opening upon expiration and closing on inhalation.