The complications of Down syndrome include:: (A) VSD, (B) ALL, (C) Hypothyroidism, (D) All of the above
Answer is D. Complications of Down syndrome are: 

Congenital cardiac defects (Most common is ventricular septal defect). 
Increased risk of leukemia particularly ALL (more commonly) and specifically the megakaryoblastic form of AML (M7-AML). 
Hypothyroidism. 
Reduced fertility in females (Males are totally infertile). 
Increased risk of respiratory tract infections.