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: Orthopaedics
In a newborn child, abduction and internal rotation produces a click sound. It is - 
Select and explain. 
A. Ortolani's sign, B. Telescoping sign, C. Lachman's sign, D. Mc Murray's sign
A: Ortolani's sign
Answer: A: Ortolani's sign 
Explanation: Barlow's test
Part 1 → Click sound (clunck) of dislocation on adduction.
Part 2 → Click sound (clunck) of reduction on abduction.
Ortolanis test

Click sound (clunk) of reduction on abduction.

Note :

If both Barlow's test and ortolani's test are given as options in the same question, go ahead with ortolani's test as some clinicians do not consider part 2 as Barlow's test.