**Core Concept**
Rabies is a viral disease caused by a lyssavirus, primarily transmitted through the saliva of infected animals, typically through a bite. The virus targets the central nervous system (CNS) of mammals, including humans.

**Why the Correct Answer is Right**
Rabies virus infects the CNS by binding to the nicotinic acetylcholine receptors (nAChRs) on the surface of neurons. The virus then undergoes replication and spreads to the CNS via retrograde axonal transport. Once inside the CNS, the virus causes inflammation and necrosis of neurons, leading to the characteristic symptoms of rabies.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because *all* mammals, including bats, dogs, cats, and humans, are susceptible to rabies infection.

**Option B:** This option is incorrect because *all* parts of the world, including urban and rural areas, are at risk for rabies transmission.

**Option C:** This option is incorrect because *all* modes of transmission, including bites, scratches, and licks on broken skin, can lead to rabies infection.

**Clinical Pearl / High-Yield Fact**
The post-exposure prophylaxis (PEP) for rabies consists of immediate wound cleaning, administration of rabies immunoglobulin (RIG), and a series of vaccinations with inactivated rabies virus. Prompt initiation of PEP is essential to prevent the development of rabies.

**Correct Answer:** D.