Which one of the following sets is correctly matched?

1. The question asks to identify the correctly matched set of diseases and their classification. 2. Set A: Diphtheria (bacterial), Pneumonia (various causes, often bacterial/viral), Leprosy (bacterial). Classified as Hereditary - Incorrect. 3. Set B: AIDS (viral), Syphilis (bacterial), Gonorrhoea (bacterial). Classified as Bacterial - Incorrect (AIDS is viral). 4. Set C: Colour blindness (usually sex linked hereditary), Haemophilia (usually sex linked hereditary), Sickle cell anaemia (autosomal recessive hereditary). Classified as Sex linked - Partially incorrect (Sickle cell is autosomal), but all are indeed hereditary genetic disorders. Among the options, this set contains diseases belonging to the broader category of genetic/hereditary conditions. 5. Set D: Polio (viral), Japanese B encephalitis (viral), Plague (bacterial). Classified as Viral - Incorrect (Plague is bacterial). 6. Comparing the sets, Set C is the only one where all listed diseases fall under the general category of hereditary/genetic disorders, making it the best fit despite the specific sub-category 'Sex linked' not applying perfectly to all three.