单选题 The physician orders IV fluid volume replacement with lactated Ringer's solution at a rate of 75 mL/hour. Using an infusion set that provides 15 gtt/mL, the nurse should calculate the flow rate to be
A. 10 gtt/min.
B. 12 gtt/min.
C. 19 gtt/min.
D. 75 gtt/min.

【正确答案】 C

【答案解析】The equation used to calculate the flow rate is: drops/minute= volume (in milliliters)×drip factor (drops/milliliter)/time (in minutes). So, the calculation is: 75mL ×15gtt/mL/60 minutes=18.75 gtt/minute=19 gtt/minute.