Ascientist claimed that hemophilia is caused by a functional deficiency in factor viii. the evidence in the passage that would best support this claim is that factor viii is:
a. a soluble blood protein. b.produced by a gene on the x chromosome. c.able to relieve hemophilia symptoms. d.encoded by a gene that contains introns.

C-able to relieve haemophilia

Explanation:

Factor  V111 is a blood clotting factor;produced in the liver and body endothelial cells. It is usually  exist as inactive form  beacuse it is  binded to glycoprotein (glycogen +protein) called  Von Willebrand factor when released into the blood stream.

If absent in the gene of certain individuals due to mutations, it result in a sex-linked conndtion called haemophilia, where blood failed to clot  when blood vessels are damaged leading to profuse bleeding/ hemorrhage.

Ideally in a normal individuals  the inactive from of factor VIII are continuously circulated in inactive forms in the blood stream, until a damaged blood vessels occurs. At the injured site they  are converted to active from called  coagulating factor VIIIa,,by separation  from Willebrand factor, react with coagulating factor IX to initiate clotting. The factor VIII is a co- factor for  factor IX, and together with calcium ion,phospholipids converts t to factor IXa,

The latter converts prothrombin to thrombin. The thrombin convert fibrinogen to fibrin, which form a stable fibrin clot at the injured site to arrest bleeding. The cascade of events is lacking individual without factor VIII. Therefore  bleeding occurs.

Consequently, symptoms of hemophilia can be relieved  by a functional factor VIII, because it will  prevent the deficiency in factor VIII in the affected individuals by acting as co-factors for the conversion of factor IX to IXa, to initiate clotting.

the correct answer is phenotype