This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vermiform Appendix, Subject name: Surgery
Earliest symptom in acute appendicitis is: 
Select and explain. 
A. Pain, B. Fever, C. Vomiting, D. Rise of pulse rate
A: Pain
Answer: A: Pain 
Explanation: Ans: a (Pain)Ref: Bailey & Love, 24th ed, p. 1206 & 23rd ed, p. 1080