**Core Concept**
The question is testing the understanding of carrier states in infectious diseases, which refers to the presence of a pathogen in an individual who is not showing symptoms but can transmit the infection to others. Carrier states are crucial in the epidemiology of infectious diseases, as they can lead to outbreaks and spread of the disease.

**Why the Correct Answer is Right**
Carrier states are common in various infections, including **Typhoid Fever**, where individuals can carry the bacteria Salmonella Typhi in their gallbladder without showing symptoms. **Hepatitis B** is another example, where individuals can be chronic carriers of the virus, transmitting it to others through bodily fluids. **Diphtheria** carriers can also spread the bacteria, Corynebacterium diphtheriae, to others. However, **Varicella (Chickenpox)** does not typically have a carrier state, as the virus usually causes a symptomatic illness in most individuals, and the immune response provides lifelong protection against future infections.

**Why Each Wrong Option is Incorrect**
**Option A:** Typhoid Fever is a classic example of a disease with a carrier state, making this option incorrect.
**Option B:** Hepatitis B is known to have a chronic carrier state, making this option incorrect.
**Option C:** Diphtheria carriers can spread the bacteria to others, making this option incorrect.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that carrier states can be asymptomatic, and individuals may not show symptoms but can still transmit the infection to others. Recognizing carrier states is crucial in infectious disease epidemiology and public health.

**Correct Answer: D. Varicella (Chickenpox)**