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: Medicine
Which one of the following is not a feature of Klinefelter's syndrome 
Select and explain. 
A. Gynecomastia, B. Eunuchoid, C. Short 4th metacarpal, D. Hypogonadism
C: Short 4th metacarpal
Answer: C: Short 4th metacarpal 
Explanation: Short 4th metacarpal is a feature of Turner syndrome.