This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Pathology
Type of hereditary hemorrhagic telangiectasia commonly associated with ALK-1 mutation is: 
Select and explain. 
A. Type 1, B. Type 2, C. Type 3, D. Type 4
B: Type 2
Answer: B: Type 2 
Explanation: B i.e. Type 2Ref: Genetic Home ReferenceExplanation:Hereditary Hemorrhagic Telangiectasia (HHT or Osler-Weber-Rendu Syndrome)Inherited disorder characterized by malformations of various blood vessels (vascular dysplasia), potentially resulting in bleeding (hemorrhage).There are totally 6 types till date.Chronic nose bleeding is usually the first sign*.Genetics.TypeMutationHHT 1ENG geneHHT 2ALK 1 geneHHT 3Unidentified gene in Ch 5 (putative)HHT 4Ch 7p14