Which of the following is a pair of viral diseases?

Options

A. common cold, AIDS
B. dysentery, common cold
C. typhoid, tuberculosis
D. ringworm, AIDS

Answer

To determine which of the following options contains a pair of viral diseases, we will analyze each option step by step:

1. **Option A: Common cold and AIDS**
- The common cold is caused by rhinoviruses, which are indeed viruses.
- AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is also a virus.
- Therefore, both diseases in this option are viral diseases.

2. **Option B: Dysentery and common cold**
- Dysentery is primarily caused by bacteria (such as Shigella or Entamoeba histolytica), making it a bacterial disease.
- The common cold, as mentioned, is a viral disease.
- Since dysentery is not viral, this option does not consist of a pair of viral diseases.

3. **Option C: Typhoid and tuberculosis**
- Typhoid fever is caused by the bacterium Salmonella Typhi, making it a bacterial disease.
- Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis, which is also a bacterial disease.
- Therefore, neither of these diseases is viral, so this option is incorrect.

4. **Option D: Ringworm and AIDS**
- Ringworm is a fungal infection caused by fungi, making it a fungal disease.
- AIDS, as stated earlier, is caused by the HIV virus, which is a viral disease.
- Since ringworm is not a viral disease, this option does not consist of a pair of viral diseases.

After analyzing all the options, we conclude that the correct answer is:

**Answer: A. Common cold and AIDS**