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
True about klinefelter syndrome is 
Select and explain. 
A. Height > arm span, B. Karyotype 45 x 0, C. Testis and sperm count are normal, D. Pubey is attained at normal age
D: Pubey is attained at normal age
Answer: D: Pubey is attained at normal age 
Explanation: Answer- D. Pubey is attained at normal ageKLINEFELTER SYNDROMEKlinefelter syndrome is the most common chromosomal disorder associated with male hypogonadkm anit infeitity.It is defined classically by a 47, XXY karyotype with variants demonstrating additional X and Y chromosomes.Pathophysiology:The addition of more than 1 extra X or Y chromosome to a male karyotypeSexual characteristics-Patients may lack secondary sexual characterstics because of a decrease in androgen production. This results in sparse facial/ body/sexual hair, a high-pitched voice. They have eunuchoid body habitus.Testicular dysgenesis (small firm testis, testis size <10 mL) may be present in postpubeal patients. Infeility/azoospermia may result from atrophy of the seminifercous tubules. Infeility is seen in practically all individuals with a 47 XXY karyotype. Patients with Klinefelter syndrome mosaicism (46,XY/ 47,XXY) can be feile.