A nurse is caring for a client who is at 36 weeks of gestation and who has a suspected placenta previa. Which of the following findings support this diagnosis?

A. Abdominal pain with scant red vaginal bleeding is incorrect because placenta previa is typically painless. Painful bleeding is more characteristic of placental abruption, not placenta previa. B. Increasing abdominal pain with a rigid abdomen is incorrect because this description aligns with placental abruption, where the placenta prematurely separates from the uterine wall, causing pain, uterine rigidity, and bleeding. C. Painless red vaginal bleeding is correct because placenta previa occurs when the placenta partially or completely covers the cervical os, leading to bright red, painless vaginal bleeding, especially in the third trimester. The uterus is usually soft and non-tender. This classic presentation is a key diagnostic clue. D. Intermittent abdominal pain following passage of bloody mucus is incorrect because this pattern is more consistent with bloody show before labor rather than placenta previa. Placenta previa bleeding is usually bright red and spontaneous, not related to cervical dilation in labor.