Final answer:
The dose should remain constant to prevent breakthrough pain for optimal pain control.
Step-by-step explanation:
The subject of this question is Health. The question is asking about the reasons for keeping the dose constant to prevent breakthrough pain. The correct option is b) for optimal pain control. Fixed or scheduled dosing around the clock offers the best pain control for clients who have severe and persistent pain. By keeping the dose constant, the pain control is optimized, ensuring that the client receives adequate relief without experiencing breakthrough pain.