This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
At what value of one hour glucose challenge test will you recommend a standard glucose tolerance test- 
Select and explain. 
A. 120 mg\/dl, B. 140 mg\/dl, C. 150 mg\/dl, D. 160 mg\/dl
B: 140 mg\/dl
Answer: B: 140 mg\/dl 
Explanation: Answer is option 2 - 140 mg/dl A serum blood glucose value greater than 140mg/dl at one hour in an one hour glucose challenge test (O&; Sullivan test) is termed suspicious and requires a formal/standard glucose tolerance test. Done to detect gestational diabetes Ref manual for laboratory and diagnostic test 8/350