Which of the following pairs contains an infectious and a non-infectious disease respectively ?

Options

A. Typhoid and AIDS
B. AIDS and cnancer
C. Pneumonia and malaria
D. Cancer and malaria

Explanation

To solve the question of which pair contains an infectious and a non-infectious disease respectively, we will analyze each option provided:

1. **Option A: Typhoid and AIDS**
- **Typhoid** is caused by the bacterium *Salmonella typhi*, making it an infectious disease.
- **AIDS** (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is also an infectious disease.
- **Conclusion**: Both are infectious diseases. This option is incorrect.

2. **Option B: AIDS and Cancer**
- **AIDS** is caused by the HIV virus, making it an infectious disease.
- **Cancer** is generally caused by mutations in DNA and is not caused by infectious agents; thus, it is a non-infectious disease.
- **Conclusion**: This option contains one infectious disease (AIDS) and one non-infectious disease (Cancer). This option is correct.

3. **Option C: Pneumonia and Malaria**
- **Pneumonia** can be caused by various pathogens, including bacteria and viruses, making it an infectious disease.
- **Malaria** is caused by the protozoan *Plasmodium*, which is also an infectious disease.
- **Conclusion**: Both are infectious diseases. This option is incorrect.

4. **Option D: Cancer and Malaria**
- **Cancer** is a non-infectious disease caused by mutations.
- **Malaria**, as mentioned, is caused by the protozoan *Plasmodium*, making it an infectious disease.
- **Conclusion**: This option contains one non-infectious disease (Cancer) and one infectious disease (Malaria). This option is incorrect.

After analyzing all the options, we find that **Option B: AIDS and Cancer** is the correct answer as it contains one infectious disease (AIDS) and one non-infectious disease (Cancer).

### Summary of the Solution:
- **Correct Answer**: Option B (AIDS - infectious, Cancer - non-infectious)