The correct answer is option 2, which matches the diseases with their respective causes as follows:

A. Thalassaemia - Haemoglobin abnormality (Option 2: A-3)

B. Typhoid - Salmonella SPS (Option 2: B-1)

C. Kala-azar - Leishmaniasis SPS (Option 2: C-2)

D. Ulcers - Heliobacter pylorus (Option 2: D-4)

Let`s dissect the other options to understand why they are incorrect:

Option 1:

A-3: Thalassaemia - Haemoglobin abnormality (correct)

B-4: Typhoid - Heliobacter pylorus (incorrect) - Alert: The cause of typhoid is Salmonella SPS, not Heliobacter pylorus.

C-2: Kala-azar - Leishmaniasis SPS (correct)

D-1: Ulcers - Salmonella SPS (incorrect) - Alert: The cause of ulcers is Heliobacter pylorus, not Salmonella SPS.

Option 3:

A-3: Thalassaemia - Haemoglobin abnormality (correct)

B-