A 58-year-old client on a mental health unit has lost control, despite having been properly medicated, and is threatening to harm himself and others. He has been placed in four- point restraints. Which nursing measure should be taken next（）
A. Release one restraint every 15 minutes.
B. Have a staff member stay with the client at all times.
C. Leave the client alone to reduce his sensory stimulation and allow him to regain control.
D. Restrict fluids until the restraint period is over.
