When assessing a multigravida on the first postpartum day, the nurse finds a moderate amount of lochia rubra, with the uterus firm, and three fingerbreadths above the umbilicus. What action should the nurse implement first?

A. Checking for a distended bladder is the priority action because a distended bladder can contribute to uterine atony and excessive bleeding postpartum. B. Reviewing the hemoglobin to determine hemorrhage may be necessary, but assessing for a distended bladder takes precedence as it can directly affect uterine tone. C. Massaging the uterus to decrease atony may be appropriate if the uterus is boggy, but in this scenario, the uterus is firm. D. Increasing intravenous infusion may be necessary if the client is hypovolemic, but assessing for a distended bladder should be done first to address potential causes of uterine atony.