Final answer:
A nurse should see the client in her 3rd trimester with signs of preterm labor first as it poses immediate risk to the mother and child, while other clients with less urgent conditions can be seen afterwards.
Step-by-step explanation:
Prioritization is a crucial skill for ambulatory care nurses, as it helps in delivering efficient and timely patient care. When considering which client to see first, the nurse should assess the urgency and potential risk associated with each patient's condition. In this scenario, the nurse would prioritize the client in her 3rd trimester who has signs of preterm labor over others. This is because preterm labor can pose immediate risks to both the mother and the unborn child, possibly leading to premature birth and the complications that can follow. The other clients presenting with a blood sugar of 150mg/dl, blood in urine 24 hours post-transurethral resection of the prostate (TURP), or a blood pressure of 140/89 mm Hg, while important, do not represent conditions that are immediately life-threatening and can be evaluated and treated after the more urgent case is addressed.