The diseases as a result of prolonged clotting is due to lack of plasma thromboplastin component (PTC) necessary to the formation of thromboplastin, is

The correct option is Christmas disease.

To understand why this is the correct answer, let us break down the blood clotting mechanism and the role of different clotting factors step-by-step:

1. Understanding the Blood Clotting Cascade:
Blood clotting (coagulation) is a complex physiological process that prevents excessive bleeding when a blood vessel is injured. It involves a cascade of chemical reactions where various inactive proteins in the blood plasma, called clotting factors, are sequentially activated.

2. Role of Thromboplastin and PTC:
Thromboplastin is a key component required to convert prothrombin into thrombin, which eventually leads to the formation of a fibrin clot. The formation of thromboplastin itself requires several clotting factors. One of these critical factors is clotting Factor IX, which is also known as plasma thromboplastin component (PTC).

3. Classification of Hemophilia:
A deficiency in these clotting factors leads to hemophilia, a genetic disorder characterized by prolonged clotting times and difficulty stopping bleeding:
- Deficiency of Factor VIII (Antihemophilic Factor A) causes Hemophilia A (Classic Hemophilia).
- Deficiency of Factor IX (Plasma Thromboplastin Component, or PTC) causes Hemophilia B, which is widely known as Christmas disease (named after Stephen Christmas, the first patient diagnosed with this specific deficiency in 1952).
- Deficiency of Factor X (Stuart-Prower factor) leads to Stuart disease (or Stuart-Prower factor deficiency).
- Deficiency of Factor II (Prothrombin) leads to Hypoprothrombinemia.

4. Conclusion:
Since the question specifically refers to a prolonged clotting disease caused by the lack of plasma thromboplastin component (PTC), it corresponds directly to Factor IX deficiency. Therefore, the disease is Christmas disease (Hemophilia B).