**Core Concept**
The incubation period of a viral infection is the time between exposure to the virus and the onset of symptoms. Hepatitis B virus (HBV) is a hepatotropic virus that causes acute and chronic liver disease. Understanding the incubation period of HBV is crucial for diagnosis, treatment, and prevention.

**Why the Correct Answer is Right**
The incubation period of HBV typically ranges from 45 to 180 days, with a median of 90 days. This duration varies depending on the dose and route of exposure. The virus enters the liver through the bloodstream, where it replicates and causes liver damage. The immune system responds by producing antibodies against HBV, which helps to clear the infection. However, in some cases, the virus can establish a chronic infection, leading to liver cirrhosis and hepatocellular carcinoma.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the incubation period of HBV is generally longer than 1-2 weeks.
**Option B:** This option is incorrect because the incubation period of HBV is not typically less than 1 month.
**Option C:** This option is incorrect because the incubation period of HBV is not typically shorter than 2-3 weeks.

**Clinical Pearl / High-Yield Fact**
The HBV incubation period can be influenced by factors such as the dose and route of exposure, as well as the host's immune status. It's essential to consider these factors when diagnosing and treating HBV infection.

**Correct Answer: C. 90 days.**