Correct Answer: A

Rationale: Ampicillin is the recommended antibiotic for treating group B streptococcus infections in pregnant women during labor to prevent neonatal infection.

Correct Answer: C

Rationale: The first action should be to discontinue the infusion of oxytocin, as it can contribute to uterine hyperstimulation and fetal distress. This allows for immediate assessment and management of the fetal heart rate.

Correct Answer: A

Rationale: Lower back pain, especially if accompanied by uterine contractions or pressure, can be a sign of preterm labor. The client should report this immediately to prevent complications or early delivery.

Correct Answer: C

Rationale: The first action is to massage the client's fundus, as uterine atony is a common cause of postpartum hemorrhage, and this intervention can help stimulate uterine contraction and reduce bleeding.

Correct Answer: B

Rationale: The nurse should initiate seizure precautions because severe preeclampsia poses a high risk for seizures (eclampsia), ensuring the safety of the client.