Concept:
Drugs are grouped by the main disease they treat. Knowing a drug's mechanism helps place it in the right class. Safinamide works by blocking the enzyme MAO-B (monoamine oxidase type B), which normally breaks down dopamine in the brain.
Step 1: Parkinson's disease is caused by a shortage of dopamine in the brain. By inhibiting MAO-B, safinamide slows the breakdown of dopamine, so more dopamine is available to relieve symptoms.
Step 2: For this reason safinamide is used as an add-on therapy (usually with levodopa) in Parkinson's disease, making it an antiparkinsonian drug.
Answer: Option (1) — Safinamide is an Antiparkinsonian drug. (1)