Correct Answer: C

Rationale: The correct answer is C: Oligohydramnios. Oligohydramnios, which is low levels of amniotic fluid, can lead to reduced cushioning in the uterus, allowing the fetus to assume abnormal positions like shoulder presentation. Macerated fetus (choice A) is related to prolonged fetal death, not shoulder presentation. Postdates pregnancy (choice B) may increase the risk of complications but is not a direct cause of shoulder presentation. Placenta abruption (choice D) is the premature separation of the placenta, which can lead to fetal distress but is not specifically linked to shoulder presentation.

Correct Answer: B

Rationale: The correct answer is B: Occipito posterior position. Forceps delivery may be indicated in this situation to help rotate the baby's head and facilitate delivery. Occipito posterior position can lead to prolonged labor and fetal distress, making forceps delivery necessary for a safe delivery. Incorrect choices: A: Cephalopelvic disproportion is not an indication for forceps delivery as it refers to mismatch between the size of the baby's head and the mother's pelvis. C: Breech presentation typically requires a different approach such as cesarean section rather than forceps delivery. D: Placenta abruption, a medical emergency, would not be managed with forceps delivery but rather require immediate intervention to prevent harm to both the mother and baby.

Correct Answer: B

Rationale: The correct answer is B: Oligohydramnios. Oligohydramnios leads to reduced volume of amniotic fluid, which can result in poor fetal movements and inadequate cushioning for the fetus. This can increase the likelihood of abnormal fetal positions like shoulder presentation. Other choices are incorrect because: A: A sub-septate uterus is a structural uterine abnormality and not directly related to shoulder presentation. C: Prematurity may lead to preterm labor but is not specifically associated with shoulder presentation. D: Multiple pregnancy can increase the risk of malpresentation but is not a direct maternal cause of shoulder presentation.

Correct Answer: D

Rationale: The correct answer is D: Elective lymph node dissection. This is because elective lymph node dissection helps to remove potentially cancerous lymph nodes, aiding in staging and ensuring complete tumor removal, thus improving the chances of curative surgery. En bloc resection (A) is important but may not always be feasible in fixed tumors. Adjuvant therapies (B) are used after surgery, not as the primary approach. Neoadjuvant therapies (C) are given before surgery to shrink tumors, not specifically for fixed tumors.

Correct Answer: B

Rationale: The correct answer is B: Hyperextension casting. The AGACNP knows that this treatment is appropriate for a condition that requires immobilization and support while allowing controlled movement. Hyperextension casting provides stability and support while promoting healing. Observation (A) would not provide adequate treatment for a condition requiring immobilization. Jewett brace (C) is typically used for spinal fractures, not for conditions that require hyperextension casting. Surgical intervention (D) would be considered if conservative measures like casting have failed.