Onset of unilateral tremors is most characteristic of which condition?

The onset of unilateral tremors is most characteristic of Parkinson's Disease because this condition often presents with resting tremors that typically start on one side of the body before they may progress to the other side. In Parkinson's Disease, these tremors are often described as "pill-rolling" movements of the fingers and are associated with other classic symptoms such as bradykinesia (slowness of movement) and rigidity.

In contrast, while multiple sclerosis can lead to tremors, they are usually not unilateral and can have various presentations due to the nature of the disease affecting the nervous system. Alzheimer's Disease is primarily associated with cognitive decline rather than tremors. Essential Tremor, while it can cause tremors, tends to be bilateral and typically occurs during voluntary movements rather than at rest, which differs from the resting tremors seen in Parkinson's Disease. Therefore, the distinct characteristic of unilateral resting tremors strongly supports the diagnosis of Parkinson's Disease.