Which of the following is a non-infectious disease?

Options

A. AIDS
B. Tuberculosis
C. Cancer
D. Typhoid

Answer

To determine which of the following is a non-infectious disease, let's analyze the options based on the definitions of infectious and non-infectious diseases.

### Step-by-Step Solution:

1. **Understand the Definitions**:
- **Infectious Diseases**: These diseases are caused by pathogens such as bacteria, viruses, fungi, or parasites. They can be transmitted from one individual to another.
- **Non-Infectious Diseases**: These diseases are not caused by infectious agents. Instead, they arise from genetic abnormalities, environmental factors, lifestyle choices, or other non-pathogenic causes.

2. **Evaluate Each Option**:
- **Option 1: AIDS**: Acquired Immunodeficiency Syndrome (AIDS) is caused by the Human Immunodeficiency Virus (HIV), which is a virus. Therefore, AIDS is an infectious disease.
- **Option 2: Tuberculosis**: This disease is caused by the bacterium Mycobacterium tuberculosis. Since it is caused by a bacterium, tuberculosis is also an infectious disease.
- **Option 3: Cancer**: Cancer is not caused by any infectious agent. It results from genetic mutations and abnormal cell growth. Therefore, cancer is classified as a non-infectious disease.
- **Option 4: Typhoid**: Typhoid fever is caused by the bacterium Salmonella typhi. Since it is caused by a bacterium, typhoid is an infectious disease.

3. **Identify the Non-Infectious Disease**:
- Based on the evaluations, the only disease that does not involve a causative infectious agent is cancer.

### Conclusion:
The correct answer is **Option 3: Cancer**, as it is a non-infectious disease.