This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Anatomy
A 35 yr old pregnant female at 40 weeks gestational age presents with pain and regular uterine contractions every 4-5min . On arrival the patient is in a lot of pain and requesting relief immediately. Her cervix is 5 cm dilated. What is most appropriate method of pain control for this patient 
Select and explain. 
A. Intramuscular morphine, B. Pudendal block, C. Local block, D. Epidural block
D: Epidural block
Answer: D: Epidural block 
Explanation: When complete relief of pain is needed throughout labor epidural analgesia is safest and simplest