This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
What is the normal value of fetal scalp pH? 
Select and explain. 
A. 6.9, B. 7, C. 7.1, D. 7.3
D: 7.3
Answer: D: 7.3 
Explanation: During labour, normal scalp blood pH is 7.25 to 7.35. A fetal scalp pH greater than or equal to 7.25 indicates a non acidotic fetus. pH value less than 7.20 indicates acidotic fetus. Vibroacoustic stimulation/Scalp stimulation: It refers to the presence of an acceleration after a vaginal examination in which examiner stimulates the fetal veex with the examining finger or after vibroacoustic stimulation confirms the absence of acidosis (pH more than 7.2). This method is preferred over fetal scalp blood sampling since this is less invasive. Ref: Danfoh's Obstetrics and Gynecology: Editors, Ronald S. Gibbs ... . By Ronald S. Gibbs, page 162.