Trisomy 21 is -: (A) Down's syndrome, (B) Turner syndrome, (C) Kleinfelter syndrome, (D) Edward syndrome
Answer is A. Ans. is 'a' i.e., Dow n's syndrome Trisomy 21 is synonymous with down's syndrome and is the most common of the chromosomal disorders o Down's syndrome - Trisomy 21 o Edwards syndrome - Trisomy 18 o Patau syndrome - Trisomy 13 o Kleinfelter syndrome - 47XXY o Turner syndrome - 45 XO